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Network management is the discipline in computing dealing with operating,managing and monitoring voice and
data networks.
Network managementis often defined as consisting offive areas,using the acronym FCAPS:
 Fault Management
 Configuration Management
 Accounting (Administration)
 Performance Management
 Security Management.
Fault Management
Faultmanagementisthe componentof networkmanagementconcernedwithdetecting,isolating
and resolvingproblems.Properlyimplemented,faultmanagementcankeepanetworkrunningatan
optimumlevel,provide ameasure of faulttolerance andminimizedowntime.A setof functions
or applicationsdesignedspecificallyforthispurpose iscalledafault-managementplatform.
Importantfunctionsof faultmanagementinclude:
 Definitionof thresholdsforpotentialfailure conditions.
 Constantmonitoringof systemstatusandusage levels.
 Continuousscanningforthreatssuchas virusesandTrojans.
 General diagnostics.
 Remote control of systemelementsincludingworkstationsandserversfromasingle location.
 Alarmsthat notifyadministratorsandusersof impendingandactual malfunctions.
 Tracing the locationsof potential andactual malfunctions.
 Automaticcorrectionof potential problem-causingconditions.
 Automaticresolutionof actual malfunctions.
 Detailedloggingof systemstatusandactionstaken.
Configuration Management
Networkconfigurationmanagement(NCM) isthe processof organizingandmaintaininginformation
aboutall the componentsof acomputernetwork.Whena networkneedsrepair,modification,
expansionorupgrading,the administratorreferstothe networkconfigurationmanagement
database to determine the bestcourse of action.Thisdatabase containsthe locationsandnetwork
addressesof all hardware devices,aswell asinformationaboutthe programs,versionsandupdates
installedinnetworkcomputers.
Networkconfigurationmanagementtoolscanbe vendor-neutral orvendor-specific.Vendor-neutral
tools,byfar the more common,are designedfornetworkscontaininghardware andprogramsfrom
multiple suppliers.Vendor-specifictoolsusuallyworkonlywiththe productsof a single company,
and can offerenhancedperformance innetworkswhere thatvendordominates.
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Advantagesof networkconfigurationmanagementinclude:
 Streamliningthe processesof maintenance,repair,expansionandupgrading.
 Minimizingconfigurationerrors.
 Minimizingdowntime.
 Optimizingnetworksecurity.
 Ensuringthat changesmade to a device orsystemdonot adverselyaffectotherdevicesor
systems.
 Rollingbackchangesto a previousconfigurationif resultsare unsatisfactory.
 Archivingthe detailsof all networkconfigurationchanges.
Accounting Management
Accounting management is the process used to measure netw orkutilization parameters so that individual or group users on the
netw orkcan be regulated appropriately for the purposes of accounting or chargeback. Similar to performance management, the
first step tow ard appropriate accounting management is to measure the utilization of all important netw orkresources.Netw ork
resource utilization can be measured using the Cisco NetFlow and Cisco IP Accounting features. Analysis of the data gathered
through these methods provides insight into current usage patterns.
A usage-based accounting and billing systemis an essentialpart of any service levelagreement (SLA). It provides both a
practicalw ay of defining obligations under an SLA and clear consequences forbehavior outside the terms of the SLA.
Performance Management Systems
Successful organizations know that to win in today’s competitive marketplace they must attract, develop, and
retain talented and productive employees. Winning organizations get their competitive edge from a
performance management system that helps them hire talented people, place them in the right position, align
their individual performance with the organization’s vision and strategic objectives, develop their abilities,
and reward performance commensurate with contributions to the organization’s success.
Benefits of Effective Performance Management
 Improved Productivity -- Improvement in both the way people work and the outcomes they produce.
 Improved Employee Morale -- Resulting from on-time performance appraisals and rewards
commensurate with employee contributions.
 Retention of Top Performers – Employees who feel accomplished in their work become
loyal employees.
 Increased Profitability – Loyal employees deliver higher levels of service that result in
customer loyalty.
TCP/IP Protocol Architecture Model
The OSI model describes idealized netw orkcommunications w ith a family of protocols. TCP/IP does not directly correspond to
this model. TCP/IP either combines severalOSI layers into a single layer, or does not use certain layers at all. The follow ing
table show sthe layers of the Oracle Solaris implementation of TCP/IP. The table lists the layers fromthe topmost layer
(application) to the bottommost layer (physicalnetwork).
Table 1–2 TCP/IP Protocol Stack
OSI Ref.
Layer No.
OSI Layer
Equivalent
TCP/IP
Layer
TCP/IP Protocol Examples
5,6,7 Application, session,
presentation
Application NFS, NIS, DNS, LDAP, telnet, ftp, rlogin, rsh, rcp,
RIP, RDISC, SNMP, and others
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OSI Ref.
Layer No.
OSI Layer
Equivalent
TCP/IP
Layer
TCP/IP Protocol Examples
4 Transport Transport TCP, UDP, SCTP
3 Netw ork Internet IPv4, IPv6, ARP, ICMP
2 Data link Data link PPP, IEEE 802.2
1 Physical Physical
netw ork
Ethernet (IEEE 802.3), Token Ring, RS-232, FDDI, and others
The table show s the TCP/IP protocollayers and the OSI model equivalents. Also show n are examples of the protocols that are
available at each level of the TCP/IP protocolstack. Each systemthat is involved in a communication transaction runs a unique
implementation of the protocolstack.
Physical Network Layer
The physical network layer specifiesthe characteristicsof the hardware to be used for the netw ork. For example, physical
netw orklayer specifies the physicalcharacteristicsof the communications media. The physicallayer of TCP/IP describes
hardw arestandardssuch as IEEE 802.3, the specification for Ethernet netw orkmedia, and RS-232, the specification for
standard pin connectors.
Data-Link Layer
The data-link layer identifies the netw orkprotocoltype of the packet, in this instance TCP/IP. The data-link layer also provides
error controland “framing.” Examples of data-link layer protocols are Ethernet IEEE 802.2 framing and Point-to-Point Protocol
(PPP) framing.
Internet Layer
The Internet layer, also know n as the network layer or IP layer, acceptsand delivers packets for the network. This layer
includes the pow erfulInternet Protocol(IP), the Address Resolution Protocol (ARP), and the Internet Control Message Protocol
(ICMP).
IP Protocol
The IP protocoland its associated routing protocols are possibly the most significant of the entire TCP/IP suite. IP is
responsible for the follow ing:
 IP addressing – The IP addressing conventions are part of the IP protocol. Designing an IPv4 Addressing
Scheme introduces IPv4 addressing and IPv6 Addressing Overview introducesIPv6 addressing.
 Host-to-hostcommunications – IP determines the path a packet must take, based on the receiving system's IP
address.
 Packet formatting– IP assembles packets into units that are know n as datagrams. Datagrams are fully described
in Internet Layer: Where Packets Are Prepared for Delivery.
 Fragmentation– If a packet is too large for transmission over the netw orkmedia, IP on the sending systembreaks the
packet into smaller fragments. IP on the receiving systemthen reconstructsthe fragments into the original packet.
Oracle Solaris supports both IPv4 and IPv6 addressing formats, which are described in this book. To avoid confusion w hen
addressing the Internet Protocol, one of the follow ing conventionsis used:
 When the term “IP” is used in a description, the description applies to both IPv4 and IPv6.
 When the term “IPv4” is used in a description, the description applies only to IPv4.
 When the term “IPv6” is used in a description, the description applies only to IPv6.
ARP Protocol
The Address Resolution Protocol (ARP) conceptually exists between the data-linkand Internet layers. ARP assists IP in
directing datagrams to the appropriate receiving systemby mapping Ethernet addresses (48 bits long) to know n IP addresses
(32 bits long).
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ICMP Protocol
The Internet Control Message Protocol (ICMP) detects and reports netw orkerror conditions. ICMP reports on the follow ing:
 Dropped packets – Packets that arrive too fast to be processed
 Connectivity failure – A destination systemcannot be reached
 Redirection – Redirecting a sending systemto use another router
Internet Control Message Protocol
From Wikipedia,the free encyclopedia
The InternetControl Message Protocol (ICMP)is one of the core protocols of the Internet Protocol Suite. It is chiefly used by
the operating systems of netw orked computers to send error messages indicating, for example, that a requested service is not
available or that a host or router could not be reached. ICMP can also be used to relay query messages.[1]
It is assigned
protocolnumber 1.[2]
ICMP[3]
differs fromtransport protocols such as TCP and UDP in that it is not typically used to exchange data betw een systems,
nor is it regularly employed by end-user networkapplications (with the exception of some diagnostic tools
like ping and traceroute).
ICMP for Internet Protocol version 4 (IPv4) is also know n as ICMPv4. IPv6 has a similar protocol, ICMPv6.
Transport Layer
The TCP/IP transport layer ensuresthat packets arrive in sequence and w ithout error, by swapping acknowledgments of data
reception, and retransmitting lost packets. This type of communication is know n as end-to-end. Transport layer protocols at
this levelare Transmission Control Protocol (TCP), User Datagram Protocol (UDP), and Stream Control Transmission Protocol
(SCTP). TCP and SCTP provide reliable, end-to-end service. UDP provides unreliable datagram service.
TCP Protocol
TCP enables applications to communicate w ith each other as though they w ere connected by a physicalcircuit. TCP sends
data in a formthat appears to be transmitted in a character-by-characterfashion, rather than as discrete packets. This
transmission consists of the following:
 Starting point, w hich opens the connection
 Entire transmission in byte order
 Ending point, w hich closes the connection.
TCP attaches a header onto the transmitted data. This header contains many parameters that help processeson the sending
systemconnect to peer processes on the receiving system.
TCP confirms that a packet has reached its destination by establishing an end-to-end connection betw een sending and
receiving hosts. TCP is therefore considered a “reliable, connection-oriented” protocol.
SCTP Protocol
SCTP is a reliable, connection-oriented transport layer protocolthat provides the same services to applications that are
available fromTCP. Moreover, SCTP can support connections between systems that have more than one address,
or multihomed. The SCTP connection betw een sending and receiving systemis called an association. Data in the
association is organized in chunks. Because SCTP supports multihoming, certain applications, particularly applications used by
the telecommunications industry, need to run over SCTP, rather than TCP.
UDP Protocol
UDP provides datagram delivery service. UDP does not verify connectionsbetweenreceiving and sending hosts. Because
UDP eliminates the processes of establishing and verifying connections,applications that send small amounts of data use
UDP.
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Application Layer
The application layer defines standardInternet services and networkapplications that anyone can use. These services work
w ith the transport layer to send and receive data. Many application layer protocols exist. The follow ing list show sexamples of
application layer protocols:
 Standard TCP/IP services such as the ftp, tftp, and telnet commands
 UNIX “r” commands, such as rlogin and rsh
 Name services, such as NIS and the domain name system(DNS)
 Directory services (LDAP)
 File services, such as the NFS service
 Simple Netw orkManagement Protocol (SNMP), w hich enables networkmanagement
 Router Discovery Server protocol(RDISC) and Routing Information Protocol (RIP) routing protocols
Standard TCP/IP Services
 FTP and Anonymous FTP – The File Transfer Protocol(FTP) transfers files to and froma remote netw ork. The protocol
includes the ftpcommand and the in.ftpd daemon. FTP enables a user to specify the name of the remote host and
file transfer command options on the localhost's command line. The in.ftpd daemon on the remote host then handles
the requests fromthe local host. Unlike rcp,ftp w orkseven when the remote computer does not run a UNIX based
operating system. A user must log in to the remote systemto make an ftp connection, unless the remote systemhas
been configured to allow anonymous FTP.
You can obtain an enormous amount of material fromanonymous FTP servers that are connected to the Internet.
Universities and other institutions set up these servers to offer software, research papers, and other information to the
public domain. When you log in to this type of server, you use the login name anonymous, hence the term “anonymous
FTP server.”
Using anonymous FTP and setting up anonymous FTP servers is outside the scope of this manual. How ever, many
books, such as The Whole InternetUser's Guide & Catalog, discussanonymous FTP in detail. Instructions for using
FTP are in System Administration Guide: Network Services. The ftp(1) man page describes all ftp command options
that are invoked through the command interpreter. Theftpd(1M) man page describes the servicesthat are provided by
the in.ftpd daemon.
 Telnet– The Telnet protocolenables terminals and terminal-oriented processesto communicate on a netw orkthat runs
TCP/IP. This protocolis implemented as the telnet program on local systems and the in.telnetd daemon on
remote machines. Telnet provides a user interface through which two hosts can communicate on a character-by-character
or line-by-line basis. Telnet includes a set of commands that are fully documented in the telnet(1) man page.
 TFTP – The Trivial File Transfer Protocol(tftp) provides functions that are similar to ftp, but the protocoldoes not
establish ftp's interactive connection. As a result, users cannot list the contents of a directory or change directories. A
user must know the fullname of the file to be copied. The tftp(1)man page describes the tftp command set.
UNIX “r” Commands
The UNIX “r” commands enable users to issue commands on their local machines that run on the remote host. These
commands include the follow ing:
 rcp
 rlogin
 rsh
Instructions for using these commands are in the rcp(1), rlogin(1), and rsh(1) man pages.
Name Services
Oracle Solaris provides the follow ing name services:
 DNS – The domain name system(DNS) is the name service provided by the Internet for TCP/IP netw orks. DNS provides
host names to the IP address service. DNS also serves as a database for mail administration. For a complete description
of this service, see System Administration Guide: Naming and DirectoryServices(DNS, NIS, and LDAP). See also
the resolver(3RESOLV) man page.
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 /etc files – The original host-based UNIX name systemw asdeveloped for standalone UNIX machines and then
adapted for netw orkuse. Many old UNIX operating systems and computers still use this system, but it is not w ellsuited for
large complex netw orks.
 NIS – Netw orkInformation Service (NIS) w as developed independently of DNS and has a slightly different focus.
Whereas DNS focuses on making communication simpler by using machine names instead of numerical IP addresses,
NIS focuses on making netw orkadministration more manageable by providing centralized controlover a variety of
netw orkinformation. NIS stores information about machine names and addresses, users, the networkitself, and netw ork
services. NIS name space information is stored in NIS maps. For more information on NIS Architecture and NIS
Administration, see System Administration Guide: Naming and DirectoryServices(DNS, NIS, and LDAP).
Directory Service
Oracle Solaris supports LDAP (Lightw eight Directory AccessProtocol) in conjunction w ith the Sun Open Net Environment (Sun
ONE) Directory Server, as w ellas other LDAP directory servers. The distinction betw een a name service and a directory
service is in the differing extent of functionality. A directory service provides the same functionality of a naming service, but
provides additional functionalities as w ell. See System Administration Guide: Naming and DirectoryServices (DNS, NIS, and
LDAP).
File Services
The NFS application layer protocolprovides file services forOracle Solaris. You can find complete information about the NFS
service in System Administration Guide: Network Services.
Network Administration
The Simple Netw orkManagement Protocol (SNMP) enables you to view the layout of your networkand the status of key
machines. SNMP also enables you to obtain complex netw orkstatisticsfromsoftware that is based on a graphicaluser
interface (GUI). Many companies offer networkmanagement packages that implement SNMP.
Routing Protocols
The Routing Information Protocol (RIP) and the Router Discovery Server Protocol(RDISC) are tw o available routing protocols
for TCP/IP netw orks. For complete lists of available routing protocols for Oracle Solaris 10, refer to Table 5–1 and Table 5–2.
What is SNMP?
• SNMP (SimpleNetwork Management Protocol) is a standard
produced by working groups within the IETF (Internet Engineering
Task Force). It is published as a setof RFCs.
• SNMP is more than a protocol. Itis a management framework,
includingan architecture,an information model, management
operations,etc.
• SNMP is the most widely used management framework today, but
many other frameworks exist.Virtually all networked devices support
SNMP.
• This presentation refers to SNMP version 1,unless stated otherwise.
We will discuss thekey extensions in versions 2 and 3.
Management information base
A management information base (MIB) is a virtual database used for managing the entities in a
communications network.Mostoften associated with the Simple Network ManagementProtocol (SNMP), the
term is also used more genericallyin contexts such as in OSI/ISO Network managementmodel.While intended
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to refer to the complete collection ofmanagementinformation available on an entity, it is often used to refer to a
particular subset,more correctlyreferred to as MIB-module.
Objects in the MIB are defined using a subsetofAbstract Syntax Notation One (ASN.1) called "Structure of
ManagementInformation Version 2 (SMIv2)" RFC 2578.The software that performs the parsing is a MIB
compiler.
The database is hierarchical (tree-structured) and entries are addressed through object
identifiers.Internetdocumentation RFCs discuss MIBs,notably RFC 1155,"Structure and Identification of
ManagementInformation for TCP/IP based internets",and its two companions, RFC 1213,"Management
Information Base for Network Managementof TCP/IP-based internets",and RFC 1157,"A Simple Network
ManagementProtocol".
A management information base (MIB) is a formal description of a set of network objects
that can be managed using the Simple Network Management Protocol (SNMP). The format
of the MIB is defined as part of the SNMP. (All other MIBs are extensions of this basic
management information base.) MIB-I refers to the initial MIB definition; MIB-II refers to
the current definition. SNMPv2 includes MIB-II and adds some new objects.
Address Resolution Protocol
Short for Address Resolution Protocol,a network layer protocol used to convert an IP address into a physical
address (called a DLC address),such as an Ethernet address.A hostwishing to obtain a physical
addressbroadcasts an ARP requestonto the TCP/IP network.The hoston the network that has the IP address in
the requestthen replies with its physical hardware address.
There is also Reverse ARP (RARP) which can be used by a hostto discover its IP address.In this case,the host
broadcasts its physical address and a RARP server replies with the host's IP address.
Address Resolution Protocol (ARP) is a telecommunications protocol used for resolution of network
layer addresses into link layer addresses, a critical function in multiple-access networks. ARP was
defined byRFC 826 in 1982.[1] It is Internet Standard STD 37. It is also the name of the program for
manipulating these addresses in most operating systems.
subnet mask
A mask used to determine what subnet an IP address belongs to.An IP address has two components,the
network address and the hostaddress.For example,consider the IP address 150.215.017.009.Assuming this is
part of a Class B network, the firsttwo numbers (150.215) representthe Class B network address,and the
second two numbers (017.009) identifya particular hoston this network.
Subnetting enables the network administrator to further divide the hostpart of the address into two or more
subnets.In this case,a part of the hostaddress is reserved to identify the particular subnet.This is easier to see
if we show the IP address in binaryformat. The full address is:
10010110.11010111.00010001.00001001
The Class B network part is:
10010110.11010111
and the hostaddress is
00010001.00001001
If this network is divided into 14 subnets,however,then the first 4 bits of the hostaddress (0001) are reserved for
identifying the subnet.
A subnet allows the flow of network traffic between hosts to be segregated based on a network configuration. By organizing
hosts into logical groups, subnetting can improve network security and performance.
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Subnet Mask
Perhaps the most recognizable aspect of subnetting is the subnet mask. Like IP addresses, a subnet mask contains four bytes
(32 bits) and is often written using the same "dotted-decimal" notation. For example, a very common subnet mask in its
binary representation
11111111 11111111 11111111 00000000
is typically shown in theequivalent, more readable form
255.255.255.0
DMI (Desktop Management Interface)
DesktopManagementInterface (DMI) isanindustryframeworkfor managingandkeepingtrackof
hardware and software componentsinasystemof personal computersfromacentral location.DMI
was createdbythe DesktopManagementTaskForce (DMTF) to automate systemmanagementand
isparticularlybeneficialinanetwork computingenvironmentwhere dozensormore computersare
managed.DMI ishardware and operatingsystem-independent,independentof specific
managementprotocol,easyforvendorstoadopt,mappable toexistingmanagementprotocolssuch
as the Simple NetworkManagementProtocol (SNMP),andusedonnetworkandnon-network
computers.DMI consistsof fourcomponents:
 ManagementInformation Format (MIF): An MIF isa textfile thatcontainsspecificinformation
aboutthe hardware andsoftware beingusedona computer.AnMIF file consistsof one ormore
groupscontainingattributes,whichdescribeeachcomponent.Bydefault,eachMIFfile contains
the standard componentIDgroup.
This groupcontainsthe productname,version,serial number,andthe time anddate of the last
installation.The IDnumberisassignedbasedonwhenthe componentwasinstalledinrelation
to othercomponents.Manufacturerscancreate theirownMIFs specifictoa component.For
example,amanufacturermightwrite anMIFfile fora fax/modemthatcontainstwogroups:a
fax group anda modemgroup.Some groupattributesinclude warrantyinformation,support
phone numbers,andanyerrorsencountered. ThisinformationisthensenttoanMIF database.
 Service layer: The service layerismemory-residentcode thatacts as a mediatorforthe
managementinterfaceandthe componentinterface andallowsmanagementandcomponent
software toaccess MIF filesin the MIFdatabase.The service layerisavailable asanoperating
systemadd-onandisa sharedresource forall programs.Because the service layermustrunall
the time,itis designednottouse a lotof memory.The service layeralsoincludesacommon
interface calledthe local agent,whichisusedtomanage individualcomponents.
 Componentinterface (CI): The CI is an applicationprograminterface (API) thatsendsstatus
informationtothe appropriate MIFfile viathe service layer.Commandsinclude the GetandSet
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commandthat modifiesthe MIFasneededandthe Eventcommandthat notifiesmanagement
software of critical events.
 Managementinterface (MI):The managementsoftware communicateswiththe service layer
usingthe MI applicationprograminterface.The MIallowsadministratorstoissue the Getand
Setcommandand the List commandthat listsall the DMI-manageable devices.
Internet Group Management Protocol
The Internet Group Management Protocol (IGMP) is a communications protocol used by hosts and
adjacent routers on IP networks to establish multicast group memberships.
IGMP is an integral part of the IP multicast specification. It is analogous
to ICMP for unicast connections. IGMP can be used for online streaming video and gaming, and
allows more efficient use of resources when supporting these types of applications.
IGMP is used on IPv4 networks. Multicast management on IPv6 networks is handled by Multicast
Listener Discovery (MLD) which uses ICMPv6 messaging contrary to IGMP's bare IP encapsulation.
A network designed to deliver a multicast service using IGMP might use this basic architecture:
IGMP is used between the client computer and a local multicast router. Switches featuring IGMP
snooping derive useful information by observing these IGMP transactions. Protocol Independent
Multicast (PIM) is then used between the local and remote multicast routers, to direct multicast traffic
from the multicast server to many multicast clients.
IGMP operates above the network layer, though it does not actually act as a transport protocol.]
Routing Information Protocol
The Routing Information Protocol (RIP) is a distance-vector routing protocol, which employs
the hop count as a routing metric. RIP prevents routing loops by implementing a limit on the number
of hops allowed in a path from the source to a destination. The maximum number of hops allowed for
RIP is 15. This hop limit, however, also limits the size of networks that RIP can support. A hop count
of 16 is considered an infinite distance and used to deprecate inaccessible, inoperable, or otherwise
undesirable routes in the selection process.
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RIP implements the split horizon, route poisoning and holddown mechanisms to prevent incorrect
routing information from being propagated. These are some of the stability features of RIP. It is also
possible to use the so called RMTI[1] (Routing Information Protocol with Metric-
based Topology Investigation) algorithm to cope with the count-to-infinity problem. With its help, it is
possible to detect every possible loop with a very small computation effort.
Limitations
 Without using RMTI, Hop count can not exceed 15, in the case that it exceeds this
limitation, it will be considered invalid.
 Most RIP networks are flat. There is no concept of areas or boundaries in RIP networks.
 Variable Length Subnet Masks were not supported by RIP version 1.
 Without using RMTI, RIP has slow convergence and count to infinity problems
Virtual private network
A virtual private network (VPN) is a network that uses primarily public telecommunication
infrastructure, such as the Internet, to provide remote offices or traveling users access to a central
organizational network.
VPNs typically require remote users of the network to be authenticated, and often secure data with
encryption technologies to prevent disclosure of private information to unauthorized parties.
VPNs may serve any network functionality that is found on any network, such as sharing of data and
access to network resources, printers, databases, websites, etc. A VPN user typically experiences the
central network in a manner that is identical to being connected directly to the central network. VPN
technology via the public Internet has replaced the need to requisition and maintain expensive
dedicated leased-line telecommunication circuits once typical in wide-area network installations.
(Desktop Management Interface) The first desktop management standard from the DMTF. Enabling PCs to be
monitored from a central console, it was superseded by the DMTF's Common Information Model (see CIM).
The Management Information File (MIF)
When a query is made to a DMI-enabled device, the memory-resident DMI agent sends back data such as model
ID, serial number, memory and port addresses in a management information file (MIF). It can also extract data
from memory to provide a current status.
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Support for SNMP
DMI can co-exist with SNMP. A single machine can serve as a proxy agent to service an entire LAN segment of
DMI machines. When SNMP queries arrive, it can transfer the data from the MIF into the SNMP's MIB
(management information base). See CIM, SNMP, WBEM and DMTF.
What is the Cisco Discovery Protocol (CDP)?
CDP is a Cisco proprietary protocol that runs on all Cisco IOS-enabled devices. It is used to gather
information about directly connected neighboring devices. CDP operates at Layer 2 of the OSI model
and is media-independent. With CDP, you can tell the hardware type, device identifier, address list,
software version, and active interfaces on neighboring Cisco devices. CDP is enabled by default on
all Cisco equipment. It uses a nonroutable SNAP frame to communicate between devices.
Note: Because CDP is media-independent it can operate over most media types. The only media
types CDP cannot operate over are X.25, because it doesn't support SNAP encapsulation, and Frame
Relay point-to-multipoint interfaces.
What are three reasons to disable CDP?
Three reasons to disable CDP are as follows:
. To save network bandwidth by not exchanging CDP frames.
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. If you are connecting to non-Cisco devices.
. Security. CDP broadcasts information about the device every 60 seconds. Sniffers and other devices
can view these broadcasts to discover information about your network.
How do you disable CDP on Cisco routers?
Two commands disable CDP on a Cisco router. To disable CDP on the entire device, use the no cdp
run global command:
RouterB(config)#no cdp run
To disable CDP on an interface only, use the no cdp enable interface command:
RouterB(config)#int e0
RouterB(config-if)#no cdp enable
This disables CDP on Ethernet interface 0.
What does the show CDP command display?
The show CDP command displays global CDP information about the device. It tells you when the
device will send CDP packets and the CDP holdtime:
RouterB#show cdp
Global CDP information:
Sending CDP packets every 60 seconds
Sending a holdtime value of 180 seconds
Note: For the CCNA test, remember that the default time a device will send out CDP information is 60
seconds and the default holdtime is 180 seconds.
On a Cisco router, what does the show cdp neighbors command display?
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The show cdp neighbors command displays the following:
· Device ID (name of the device)
· The local interface (local outgoing port)
· The holdtime displayed in seconds
· The device's capability code (this tells you if the device is a router, switch, or repeater)
· Hardware platform of the neighboring device (what type of Cisco device it is and the model)
· Port ID of the neighboring device (remote port)
RouterB#show cdp neighbors
Capability Codes:
R - Router, T - Trans Bridge, B - Source Route Bridge
S - Switch, H - Host, I - IGMP, r - Repeater
Device ID Local Intrfce Holdtme Capability Platform Port ID
RouterA Ser 0 146 R 2505 Ser 0
What does the show cdp neighbors detail command display?
The show cdp neighbors detail and show cdp entry * commands show the same output. They both
display the following:
· Device ID (host name) of the remote neighbor
· Layer 3 address of the remote device (if the device has more than one Layer 3 address on its
interface, only the primary address is shown)
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· Device platform and capabilities· Local interface and outgoing port ID
· Remote device holdtime in seconds
· IOS type and version
RouterB#show cdp neighbors detail
-------------------------
Device ID: RouterA
Entry address(es):
IP address: 192.168.2.1
Platform: cisco 2505, Capabilities: Router
Interface: Serial1, Port ID (outgoing port): Serial1
Holdtime : 164 sec Version :Cisco Internetwork Operating System Software
IOS (tm) 2500 Software (C2500-D-L), Version 12.0(13), RELEASE SOFTWARE
(fc1)Copyright (c) 1986-2000 by cisco Systems, Inc.Compiled Wed 06-Sep-00 01:08 by Linda
What does the show cdp traffic command display?
The show cdp traffic command displays information about interface traffic. This includes the number
of CDP packets sent and received and CDP errors:
RouterB#show cdp traffic
CDP counters :
Packets output: 105, Input: 103
15
Hdr syntax: 0, Chksum error: 0, Encaps failed:
No memory: 0, Invalid packet: 0, Fragmented: 0
What does the show cdp interface command display?
The show cdp interface command displays the status of CDP on all interfaces on your device:
RouterB#show cdp interface
Ethernet0 is up, line protocol is down
Encapsulation ARPA
Sending CDP packets every 60 seconds Holdtime is 180 seconds
Serial0 is up, line protocol is up
Encapsulation HDLC
Sending CDP packets every 60 seconds Holdtime is 180 seconds
Serial1 is up, line protocol is up
Encapsulation HDLC
Sending CDP packets every 60 seconds Holdtime is 180 seconds
What Cisco IOS router command can you use to see a neighbor router's IP address?
To see a neighbor router's IP address, you must use the show cdp neighbor detail or show cdp entry *
user mode or EXEC command. (This one will probably be on the exam)
What IOS command do you use to view the active outbound telnet sessions for the current user on a
Cisco router?
16
The show sessions command displays the active outbound telnet sessions from that particular user
on your router.
RouterA#show sessions
Conn Host Address Byte Idle Conn Name
* 1 192.168.1.2 192.168.1.2 0 0 192.168.1.2
What key sequence do you use to suspend a Telnet session on a remote system and return to your
local router?
To suspend a Telnet session, press Ctrl-Shift-6, and then press X.
How do you end a remote Telnet session on a Cisco router?
To end a Telnet session, use the exit or logout command while you're on the remote device:
RouterB>exit
[Connection to 192.168.1.2 closed by foreign host]
RouterA#
Upon using the ping EXEC command, you receive one of the following responses:
· .
· !
· ?
· C
· U
17
· I
What does each of these responses mean?
. = Each period indicates that the network server timed out while waiting for a reply.
! =Each exclamation point indicates the receipt of a reply.
? =Unknown packet type.
C =A congestion experienced packet was received.
U =A destination unreachable error PDU was received.
I = The user interrupted the test.
What is the trace EXEC command used for?
RouterA#trace 192.168.2.2
Type escape sequence to abort.
Tracing the route to 192.168.2.2
1 192.168.2.2 16 msec 16 msec *
Note: If trace responds with a * it means the probe timed out. If it responds with a ? it means it
received an unknown packet type.
What are the two ways in which a Cisco router resolves host names to IP addresses?
A Cisco router resolves host names using either a host table on each router or a DNS server.
What is the main purpose of RAM on a Cisco router?
On most Cisco routers, the IOS is loaded into RAM, as well as the running configuration. It is also
used to hold routing tables and packet buffers.
18
What is the function of ROM on a Cisco router?
On a Cisco router, ROM is used to start and maintain the router.
What is Flash memory used for on a Cisco router?
Flash memory is used to store the Cisco IOS software image and, if there is room, multiple
configuration files or multiple IOS files. On some routers (the 2500 series), it is also used to run the
IOS.
What is the function of NVRAM on a Cisco router?
Nonvolatile Random-Access Memory (NVRAM) is used to hold the saved router configuration. This
configuration is not lost when the router is turned off or reloaded.
What is the main purpose of the configuration register on a Cisco router?
The configuration register's main purpose is to control how the router boots up. It is a 16-bit software
register that by default is set to load the Cisco IOS from Flash memory and to look for and load the
startup-config file from NVRAM.
What Cisco IOS command would you use to view the current configuration register value?
The show version command is used to display the router's current configuration register:
RouterA#show version
Cisco Internetwork Operating System SoftwareIOS (tm) 2500 Software (C2500-D-L),
Version 12.0(13), RELEASE SOFTWARE (fc1)Copyright (c) 1986-2000 by cisco Systems,
Inc.Compiled Wed 06-Sep-00 01:08 by lindaImage text-base: 0x030388F8, data-base: 0x00001000
Configuration register is 0x2102
How do you change the configuration register on a Cisco router?
To change the configuration register on a Cisco router, use the config-register global command.
19
What Cisco IOS command displays the contents of Flash memory?
The show flash command displays the contents of Flash memory. This includes the images stored in
Flash memory, the images' names, bytes used in Flash memory, bytes available, and the total
amount of Flash memory on your router:
RouterA#show flash
System flash directory:File Length Name/status
1 6897716 c2500-d-l.120-13.bin[6897780 bytes used, 1490828 available, 8388608 total]8192K bytes
of processor board System flash (Read ONLY)
What IOS command would you use to copy the running configuration on a router to a TFTP server?
To copy the running configuration to a TFTP server, use the copy running-config tftp privileged EXEC
command:
RouterB#copy run tftp
Address or name of remote host []? 192.168.0.2
Destination filename [routerb-confg]?
!!
780 bytes copied in 6.900 secs (130 bytes/sec)
This gives you a backup of your running config on a TFTP server.
How do you erase the router's configuration and bring it back to the factory default?
The erase startup-config privileged EXEC command erases your router's configuration, thus bringing
it back to its factory defaults:
RouterB#erase startup-config
20
Erasing the nvram filesystem will remove all files! Continue? [confirm]
[OK]Erase of nvram: complete
Note: In order to complete the process, you need to reload the router. An older IOS command that
you can use to accomplish the same results is write erase.
How do you restore a configuration file from a TFTP server into your Cisco router's RAM?
The copy tftp running-config privileged EXEC command merges the saved and running configuration
into your router's RAM, so any commands not explicitly change or removed will remain in the running
configuration.
RouterB#copy tftp running-config
Address or name of remote host []? 192.168.0.2
Source filename []? routerb-confg
Destination filename [running-config]?
Accessing tftp://192.168.0.2/routerb-confg...
Loading routerb-confg from 192.168.0.2 (via Ethernet0):
!
[OK - 780/1024 bytes] 780 bytes copied in 4.12 secs (195 bytes/sec)
RouterB# 01:40:46: %SYS-5-CONFIG: Configured from tftp://192.168.0.2/routerb-confg
How do you back up a Cisco router IOS?
To back up the current IOS image on your router, use the copy flash tftp privileged EXEC mode
command:
RouterB#copy flash tftp
21
Source filename [routerb-flash]? flash:c2500-d-l.120-13.bin
Address or name of remote host []? 192.168.0.2
Destination filename [c2500-d-l.120-13.bin]?
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!6897716 bytes copied in 90.856 secs
(76641 bytes/sec)
How do you upgrade or restore the Cisco router IOS?
To upgrade or restore the Cisco router IOS, use the copy tftp flash privileged EXEC mode command.
How you make a Cisco router a TFTP server?
To configure a Cisco router as a TFTP server, use the tftp-server global configuration command.
What is the boot sequence of a Cisco router?
The boot sequence of a router is as follows:
hardware /power on
load run bootstrapfind the IOS software
load the softwarefind the config (default NVRAM)
load the configuration (startup-config) into RAM
Run the IOS
What can you configure on a router in setup mode?
ip addresses
22
routed protocols
enable password
Important Config Register Notes:
2100 manual boot rommon>
2101 boot from ROM
2102 normal/password recovery
2105 boot system command - config-register NVRAM
2142 bypass NVRAM
ctrl-break = ROM monitor mode
router(config)#boot system flash ios filename
router(config)#boot system tftp filename ip address
router(config)#boot system ROM
Note the router prompt for boot commands. Copy commands = router#
(Used only for educational purpose)
Ammad khan

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NETWORK MANAGEMENT - 2015

  • 1. 1 Network management is the discipline in computing dealing with operating,managing and monitoring voice and data networks. Network managementis often defined as consisting offive areas,using the acronym FCAPS:  Fault Management  Configuration Management  Accounting (Administration)  Performance Management  Security Management. Fault Management Faultmanagementisthe componentof networkmanagementconcernedwithdetecting,isolating and resolvingproblems.Properlyimplemented,faultmanagementcankeepanetworkrunningatan optimumlevel,provide ameasure of faulttolerance andminimizedowntime.A setof functions or applicationsdesignedspecificallyforthispurpose iscalledafault-managementplatform. Importantfunctionsof faultmanagementinclude:  Definitionof thresholdsforpotentialfailure conditions.  Constantmonitoringof systemstatusandusage levels.  Continuousscanningforthreatssuchas virusesandTrojans.  General diagnostics.  Remote control of systemelementsincludingworkstationsandserversfromasingle location.  Alarmsthat notifyadministratorsandusersof impendingandactual malfunctions.  Tracing the locationsof potential andactual malfunctions.  Automaticcorrectionof potential problem-causingconditions.  Automaticresolutionof actual malfunctions.  Detailedloggingof systemstatusandactionstaken. Configuration Management Networkconfigurationmanagement(NCM) isthe processof organizingandmaintaininginformation aboutall the componentsof acomputernetwork.Whena networkneedsrepair,modification, expansionorupgrading,the administratorreferstothe networkconfigurationmanagement database to determine the bestcourse of action.Thisdatabase containsthe locationsandnetwork addressesof all hardware devices,aswell asinformationaboutthe programs,versionsandupdates installedinnetworkcomputers. Networkconfigurationmanagementtoolscanbe vendor-neutral orvendor-specific.Vendor-neutral tools,byfar the more common,are designedfornetworkscontaininghardware andprogramsfrom multiple suppliers.Vendor-specifictoolsusuallyworkonlywiththe productsof a single company, and can offerenhancedperformance innetworkswhere thatvendordominates.
  • 2. 2 Advantagesof networkconfigurationmanagementinclude:  Streamliningthe processesof maintenance,repair,expansionandupgrading.  Minimizingconfigurationerrors.  Minimizingdowntime.  Optimizingnetworksecurity.  Ensuringthat changesmade to a device orsystemdonot adverselyaffectotherdevicesor systems.  Rollingbackchangesto a previousconfigurationif resultsare unsatisfactory.  Archivingthe detailsof all networkconfigurationchanges. Accounting Management Accounting management is the process used to measure netw orkutilization parameters so that individual or group users on the netw orkcan be regulated appropriately for the purposes of accounting or chargeback. Similar to performance management, the first step tow ard appropriate accounting management is to measure the utilization of all important netw orkresources.Netw ork resource utilization can be measured using the Cisco NetFlow and Cisco IP Accounting features. Analysis of the data gathered through these methods provides insight into current usage patterns. A usage-based accounting and billing systemis an essentialpart of any service levelagreement (SLA). It provides both a practicalw ay of defining obligations under an SLA and clear consequences forbehavior outside the terms of the SLA. Performance Management Systems Successful organizations know that to win in today’s competitive marketplace they must attract, develop, and retain talented and productive employees. Winning organizations get their competitive edge from a performance management system that helps them hire talented people, place them in the right position, align their individual performance with the organization’s vision and strategic objectives, develop their abilities, and reward performance commensurate with contributions to the organization’s success. Benefits of Effective Performance Management  Improved Productivity -- Improvement in both the way people work and the outcomes they produce.  Improved Employee Morale -- Resulting from on-time performance appraisals and rewards commensurate with employee contributions.  Retention of Top Performers – Employees who feel accomplished in their work become loyal employees.  Increased Profitability – Loyal employees deliver higher levels of service that result in customer loyalty. TCP/IP Protocol Architecture Model The OSI model describes idealized netw orkcommunications w ith a family of protocols. TCP/IP does not directly correspond to this model. TCP/IP either combines severalOSI layers into a single layer, or does not use certain layers at all. The follow ing table show sthe layers of the Oracle Solaris implementation of TCP/IP. The table lists the layers fromthe topmost layer (application) to the bottommost layer (physicalnetwork). Table 1–2 TCP/IP Protocol Stack OSI Ref. Layer No. OSI Layer Equivalent TCP/IP Layer TCP/IP Protocol Examples 5,6,7 Application, session, presentation Application NFS, NIS, DNS, LDAP, telnet, ftp, rlogin, rsh, rcp, RIP, RDISC, SNMP, and others
  • 3. 3 OSI Ref. Layer No. OSI Layer Equivalent TCP/IP Layer TCP/IP Protocol Examples 4 Transport Transport TCP, UDP, SCTP 3 Netw ork Internet IPv4, IPv6, ARP, ICMP 2 Data link Data link PPP, IEEE 802.2 1 Physical Physical netw ork Ethernet (IEEE 802.3), Token Ring, RS-232, FDDI, and others The table show s the TCP/IP protocollayers and the OSI model equivalents. Also show n are examples of the protocols that are available at each level of the TCP/IP protocolstack. Each systemthat is involved in a communication transaction runs a unique implementation of the protocolstack. Physical Network Layer The physical network layer specifiesthe characteristicsof the hardware to be used for the netw ork. For example, physical netw orklayer specifies the physicalcharacteristicsof the communications media. The physicallayer of TCP/IP describes hardw arestandardssuch as IEEE 802.3, the specification for Ethernet netw orkmedia, and RS-232, the specification for standard pin connectors. Data-Link Layer The data-link layer identifies the netw orkprotocoltype of the packet, in this instance TCP/IP. The data-link layer also provides error controland “framing.” Examples of data-link layer protocols are Ethernet IEEE 802.2 framing and Point-to-Point Protocol (PPP) framing. Internet Layer The Internet layer, also know n as the network layer or IP layer, acceptsand delivers packets for the network. This layer includes the pow erfulInternet Protocol(IP), the Address Resolution Protocol (ARP), and the Internet Control Message Protocol (ICMP). IP Protocol The IP protocoland its associated routing protocols are possibly the most significant of the entire TCP/IP suite. IP is responsible for the follow ing:  IP addressing – The IP addressing conventions are part of the IP protocol. Designing an IPv4 Addressing Scheme introduces IPv4 addressing and IPv6 Addressing Overview introducesIPv6 addressing.  Host-to-hostcommunications – IP determines the path a packet must take, based on the receiving system's IP address.  Packet formatting– IP assembles packets into units that are know n as datagrams. Datagrams are fully described in Internet Layer: Where Packets Are Prepared for Delivery.  Fragmentation– If a packet is too large for transmission over the netw orkmedia, IP on the sending systembreaks the packet into smaller fragments. IP on the receiving systemthen reconstructsthe fragments into the original packet. Oracle Solaris supports both IPv4 and IPv6 addressing formats, which are described in this book. To avoid confusion w hen addressing the Internet Protocol, one of the follow ing conventionsis used:  When the term “IP” is used in a description, the description applies to both IPv4 and IPv6.  When the term “IPv4” is used in a description, the description applies only to IPv4.  When the term “IPv6” is used in a description, the description applies only to IPv6. ARP Protocol The Address Resolution Protocol (ARP) conceptually exists between the data-linkand Internet layers. ARP assists IP in directing datagrams to the appropriate receiving systemby mapping Ethernet addresses (48 bits long) to know n IP addresses (32 bits long).
  • 4. 4 ICMP Protocol The Internet Control Message Protocol (ICMP) detects and reports netw orkerror conditions. ICMP reports on the follow ing:  Dropped packets – Packets that arrive too fast to be processed  Connectivity failure – A destination systemcannot be reached  Redirection – Redirecting a sending systemto use another router Internet Control Message Protocol From Wikipedia,the free encyclopedia The InternetControl Message Protocol (ICMP)is one of the core protocols of the Internet Protocol Suite. It is chiefly used by the operating systems of netw orked computers to send error messages indicating, for example, that a requested service is not available or that a host or router could not be reached. ICMP can also be used to relay query messages.[1] It is assigned protocolnumber 1.[2] ICMP[3] differs fromtransport protocols such as TCP and UDP in that it is not typically used to exchange data betw een systems, nor is it regularly employed by end-user networkapplications (with the exception of some diagnostic tools like ping and traceroute). ICMP for Internet Protocol version 4 (IPv4) is also know n as ICMPv4. IPv6 has a similar protocol, ICMPv6. Transport Layer The TCP/IP transport layer ensuresthat packets arrive in sequence and w ithout error, by swapping acknowledgments of data reception, and retransmitting lost packets. This type of communication is know n as end-to-end. Transport layer protocols at this levelare Transmission Control Protocol (TCP), User Datagram Protocol (UDP), and Stream Control Transmission Protocol (SCTP). TCP and SCTP provide reliable, end-to-end service. UDP provides unreliable datagram service. TCP Protocol TCP enables applications to communicate w ith each other as though they w ere connected by a physicalcircuit. TCP sends data in a formthat appears to be transmitted in a character-by-characterfashion, rather than as discrete packets. This transmission consists of the following:  Starting point, w hich opens the connection  Entire transmission in byte order  Ending point, w hich closes the connection. TCP attaches a header onto the transmitted data. This header contains many parameters that help processeson the sending systemconnect to peer processes on the receiving system. TCP confirms that a packet has reached its destination by establishing an end-to-end connection betw een sending and receiving hosts. TCP is therefore considered a “reliable, connection-oriented” protocol. SCTP Protocol SCTP is a reliable, connection-oriented transport layer protocolthat provides the same services to applications that are available fromTCP. Moreover, SCTP can support connections between systems that have more than one address, or multihomed. The SCTP connection betw een sending and receiving systemis called an association. Data in the association is organized in chunks. Because SCTP supports multihoming, certain applications, particularly applications used by the telecommunications industry, need to run over SCTP, rather than TCP. UDP Protocol UDP provides datagram delivery service. UDP does not verify connectionsbetweenreceiving and sending hosts. Because UDP eliminates the processes of establishing and verifying connections,applications that send small amounts of data use UDP.
  • 5. 5 Application Layer The application layer defines standardInternet services and networkapplications that anyone can use. These services work w ith the transport layer to send and receive data. Many application layer protocols exist. The follow ing list show sexamples of application layer protocols:  Standard TCP/IP services such as the ftp, tftp, and telnet commands  UNIX “r” commands, such as rlogin and rsh  Name services, such as NIS and the domain name system(DNS)  Directory services (LDAP)  File services, such as the NFS service  Simple Netw orkManagement Protocol (SNMP), w hich enables networkmanagement  Router Discovery Server protocol(RDISC) and Routing Information Protocol (RIP) routing protocols Standard TCP/IP Services  FTP and Anonymous FTP – The File Transfer Protocol(FTP) transfers files to and froma remote netw ork. The protocol includes the ftpcommand and the in.ftpd daemon. FTP enables a user to specify the name of the remote host and file transfer command options on the localhost's command line. The in.ftpd daemon on the remote host then handles the requests fromthe local host. Unlike rcp,ftp w orkseven when the remote computer does not run a UNIX based operating system. A user must log in to the remote systemto make an ftp connection, unless the remote systemhas been configured to allow anonymous FTP. You can obtain an enormous amount of material fromanonymous FTP servers that are connected to the Internet. Universities and other institutions set up these servers to offer software, research papers, and other information to the public domain. When you log in to this type of server, you use the login name anonymous, hence the term “anonymous FTP server.” Using anonymous FTP and setting up anonymous FTP servers is outside the scope of this manual. How ever, many books, such as The Whole InternetUser's Guide & Catalog, discussanonymous FTP in detail. Instructions for using FTP are in System Administration Guide: Network Services. The ftp(1) man page describes all ftp command options that are invoked through the command interpreter. Theftpd(1M) man page describes the servicesthat are provided by the in.ftpd daemon.  Telnet– The Telnet protocolenables terminals and terminal-oriented processesto communicate on a netw orkthat runs TCP/IP. This protocolis implemented as the telnet program on local systems and the in.telnetd daemon on remote machines. Telnet provides a user interface through which two hosts can communicate on a character-by-character or line-by-line basis. Telnet includes a set of commands that are fully documented in the telnet(1) man page.  TFTP – The Trivial File Transfer Protocol(tftp) provides functions that are similar to ftp, but the protocoldoes not establish ftp's interactive connection. As a result, users cannot list the contents of a directory or change directories. A user must know the fullname of the file to be copied. The tftp(1)man page describes the tftp command set. UNIX “r” Commands The UNIX “r” commands enable users to issue commands on their local machines that run on the remote host. These commands include the follow ing:  rcp  rlogin  rsh Instructions for using these commands are in the rcp(1), rlogin(1), and rsh(1) man pages. Name Services Oracle Solaris provides the follow ing name services:  DNS – The domain name system(DNS) is the name service provided by the Internet for TCP/IP netw orks. DNS provides host names to the IP address service. DNS also serves as a database for mail administration. For a complete description of this service, see System Administration Guide: Naming and DirectoryServices(DNS, NIS, and LDAP). See also the resolver(3RESOLV) man page.
  • 6. 6  /etc files – The original host-based UNIX name systemw asdeveloped for standalone UNIX machines and then adapted for netw orkuse. Many old UNIX operating systems and computers still use this system, but it is not w ellsuited for large complex netw orks.  NIS – Netw orkInformation Service (NIS) w as developed independently of DNS and has a slightly different focus. Whereas DNS focuses on making communication simpler by using machine names instead of numerical IP addresses, NIS focuses on making netw orkadministration more manageable by providing centralized controlover a variety of netw orkinformation. NIS stores information about machine names and addresses, users, the networkitself, and netw ork services. NIS name space information is stored in NIS maps. For more information on NIS Architecture and NIS Administration, see System Administration Guide: Naming and DirectoryServices(DNS, NIS, and LDAP). Directory Service Oracle Solaris supports LDAP (Lightw eight Directory AccessProtocol) in conjunction w ith the Sun Open Net Environment (Sun ONE) Directory Server, as w ellas other LDAP directory servers. The distinction betw een a name service and a directory service is in the differing extent of functionality. A directory service provides the same functionality of a naming service, but provides additional functionalities as w ell. See System Administration Guide: Naming and DirectoryServices (DNS, NIS, and LDAP). File Services The NFS application layer protocolprovides file services forOracle Solaris. You can find complete information about the NFS service in System Administration Guide: Network Services. Network Administration The Simple Netw orkManagement Protocol (SNMP) enables you to view the layout of your networkand the status of key machines. SNMP also enables you to obtain complex netw orkstatisticsfromsoftware that is based on a graphicaluser interface (GUI). Many companies offer networkmanagement packages that implement SNMP. Routing Protocols The Routing Information Protocol (RIP) and the Router Discovery Server Protocol(RDISC) are tw o available routing protocols for TCP/IP netw orks. For complete lists of available routing protocols for Oracle Solaris 10, refer to Table 5–1 and Table 5–2. What is SNMP? • SNMP (SimpleNetwork Management Protocol) is a standard produced by working groups within the IETF (Internet Engineering Task Force). It is published as a setof RFCs. • SNMP is more than a protocol. Itis a management framework, includingan architecture,an information model, management operations,etc. • SNMP is the most widely used management framework today, but many other frameworks exist.Virtually all networked devices support SNMP. • This presentation refers to SNMP version 1,unless stated otherwise. We will discuss thekey extensions in versions 2 and 3. Management information base A management information base (MIB) is a virtual database used for managing the entities in a communications network.Mostoften associated with the Simple Network ManagementProtocol (SNMP), the term is also used more genericallyin contexts such as in OSI/ISO Network managementmodel.While intended
  • 7. 7 to refer to the complete collection ofmanagementinformation available on an entity, it is often used to refer to a particular subset,more correctlyreferred to as MIB-module. Objects in the MIB are defined using a subsetofAbstract Syntax Notation One (ASN.1) called "Structure of ManagementInformation Version 2 (SMIv2)" RFC 2578.The software that performs the parsing is a MIB compiler. The database is hierarchical (tree-structured) and entries are addressed through object identifiers.Internetdocumentation RFCs discuss MIBs,notably RFC 1155,"Structure and Identification of ManagementInformation for TCP/IP based internets",and its two companions, RFC 1213,"Management Information Base for Network Managementof TCP/IP-based internets",and RFC 1157,"A Simple Network ManagementProtocol". A management information base (MIB) is a formal description of a set of network objects that can be managed using the Simple Network Management Protocol (SNMP). The format of the MIB is defined as part of the SNMP. (All other MIBs are extensions of this basic management information base.) MIB-I refers to the initial MIB definition; MIB-II refers to the current definition. SNMPv2 includes MIB-II and adds some new objects. Address Resolution Protocol Short for Address Resolution Protocol,a network layer protocol used to convert an IP address into a physical address (called a DLC address),such as an Ethernet address.A hostwishing to obtain a physical addressbroadcasts an ARP requestonto the TCP/IP network.The hoston the network that has the IP address in the requestthen replies with its physical hardware address. There is also Reverse ARP (RARP) which can be used by a hostto discover its IP address.In this case,the host broadcasts its physical address and a RARP server replies with the host's IP address. Address Resolution Protocol (ARP) is a telecommunications protocol used for resolution of network layer addresses into link layer addresses, a critical function in multiple-access networks. ARP was defined byRFC 826 in 1982.[1] It is Internet Standard STD 37. It is also the name of the program for manipulating these addresses in most operating systems. subnet mask A mask used to determine what subnet an IP address belongs to.An IP address has two components,the network address and the hostaddress.For example,consider the IP address 150.215.017.009.Assuming this is part of a Class B network, the firsttwo numbers (150.215) representthe Class B network address,and the second two numbers (017.009) identifya particular hoston this network. Subnetting enables the network administrator to further divide the hostpart of the address into two or more subnets.In this case,a part of the hostaddress is reserved to identify the particular subnet.This is easier to see if we show the IP address in binaryformat. The full address is: 10010110.11010111.00010001.00001001 The Class B network part is: 10010110.11010111 and the hostaddress is 00010001.00001001 If this network is divided into 14 subnets,however,then the first 4 bits of the hostaddress (0001) are reserved for identifying the subnet. A subnet allows the flow of network traffic between hosts to be segregated based on a network configuration. By organizing hosts into logical groups, subnetting can improve network security and performance.
  • 8. 8 Subnet Mask Perhaps the most recognizable aspect of subnetting is the subnet mask. Like IP addresses, a subnet mask contains four bytes (32 bits) and is often written using the same "dotted-decimal" notation. For example, a very common subnet mask in its binary representation 11111111 11111111 11111111 00000000 is typically shown in theequivalent, more readable form 255.255.255.0 DMI (Desktop Management Interface) DesktopManagementInterface (DMI) isanindustryframeworkfor managingandkeepingtrackof hardware and software componentsinasystemof personal computersfromacentral location.DMI was createdbythe DesktopManagementTaskForce (DMTF) to automate systemmanagementand isparticularlybeneficialinanetwork computingenvironmentwhere dozensormore computersare managed.DMI ishardware and operatingsystem-independent,independentof specific managementprotocol,easyforvendorstoadopt,mappable toexistingmanagementprotocolssuch as the Simple NetworkManagementProtocol (SNMP),andusedonnetworkandnon-network computers.DMI consistsof fourcomponents:  ManagementInformation Format (MIF): An MIF isa textfile thatcontainsspecificinformation aboutthe hardware andsoftware beingusedona computer.AnMIF file consistsof one ormore groupscontainingattributes,whichdescribeeachcomponent.Bydefault,eachMIFfile contains the standard componentIDgroup. This groupcontainsthe productname,version,serial number,andthe time anddate of the last installation.The IDnumberisassignedbasedonwhenthe componentwasinstalledinrelation to othercomponents.Manufacturerscancreate theirownMIFs specifictoa component.For example,amanufacturermightwrite anMIFfile fora fax/modemthatcontainstwogroups:a fax group anda modemgroup.Some groupattributesinclude warrantyinformation,support phone numbers,andanyerrorsencountered. ThisinformationisthensenttoanMIF database.  Service layer: The service layerismemory-residentcode thatacts as a mediatorforthe managementinterfaceandthe componentinterface andallowsmanagementandcomponent software toaccess MIF filesin the MIFdatabase.The service layerisavailable asanoperating systemadd-onandisa sharedresource forall programs.Because the service layermustrunall the time,itis designednottouse a lotof memory.The service layeralsoincludesacommon interface calledthe local agent,whichisusedtomanage individualcomponents.  Componentinterface (CI): The CI is an applicationprograminterface (API) thatsendsstatus informationtothe appropriate MIFfile viathe service layer.Commandsinclude the GetandSet
  • 9. 9 commandthat modifiesthe MIFasneededandthe Eventcommandthat notifiesmanagement software of critical events.  Managementinterface (MI):The managementsoftware communicateswiththe service layer usingthe MI applicationprograminterface.The MIallowsadministratorstoissue the Getand Setcommandand the List commandthat listsall the DMI-manageable devices. Internet Group Management Protocol The Internet Group Management Protocol (IGMP) is a communications protocol used by hosts and adjacent routers on IP networks to establish multicast group memberships. IGMP is an integral part of the IP multicast specification. It is analogous to ICMP for unicast connections. IGMP can be used for online streaming video and gaming, and allows more efficient use of resources when supporting these types of applications. IGMP is used on IPv4 networks. Multicast management on IPv6 networks is handled by Multicast Listener Discovery (MLD) which uses ICMPv6 messaging contrary to IGMP's bare IP encapsulation. A network designed to deliver a multicast service using IGMP might use this basic architecture: IGMP is used between the client computer and a local multicast router. Switches featuring IGMP snooping derive useful information by observing these IGMP transactions. Protocol Independent Multicast (PIM) is then used between the local and remote multicast routers, to direct multicast traffic from the multicast server to many multicast clients. IGMP operates above the network layer, though it does not actually act as a transport protocol.] Routing Information Protocol The Routing Information Protocol (RIP) is a distance-vector routing protocol, which employs the hop count as a routing metric. RIP prevents routing loops by implementing a limit on the number of hops allowed in a path from the source to a destination. The maximum number of hops allowed for RIP is 15. This hop limit, however, also limits the size of networks that RIP can support. A hop count of 16 is considered an infinite distance and used to deprecate inaccessible, inoperable, or otherwise undesirable routes in the selection process.
  • 10. 10 RIP implements the split horizon, route poisoning and holddown mechanisms to prevent incorrect routing information from being propagated. These are some of the stability features of RIP. It is also possible to use the so called RMTI[1] (Routing Information Protocol with Metric- based Topology Investigation) algorithm to cope with the count-to-infinity problem. With its help, it is possible to detect every possible loop with a very small computation effort. Limitations  Without using RMTI, Hop count can not exceed 15, in the case that it exceeds this limitation, it will be considered invalid.  Most RIP networks are flat. There is no concept of areas or boundaries in RIP networks.  Variable Length Subnet Masks were not supported by RIP version 1.  Without using RMTI, RIP has slow convergence and count to infinity problems Virtual private network A virtual private network (VPN) is a network that uses primarily public telecommunication infrastructure, such as the Internet, to provide remote offices or traveling users access to a central organizational network. VPNs typically require remote users of the network to be authenticated, and often secure data with encryption technologies to prevent disclosure of private information to unauthorized parties. VPNs may serve any network functionality that is found on any network, such as sharing of data and access to network resources, printers, databases, websites, etc. A VPN user typically experiences the central network in a manner that is identical to being connected directly to the central network. VPN technology via the public Internet has replaced the need to requisition and maintain expensive dedicated leased-line telecommunication circuits once typical in wide-area network installations. (Desktop Management Interface) The first desktop management standard from the DMTF. Enabling PCs to be monitored from a central console, it was superseded by the DMTF's Common Information Model (see CIM). The Management Information File (MIF) When a query is made to a DMI-enabled device, the memory-resident DMI agent sends back data such as model ID, serial number, memory and port addresses in a management information file (MIF). It can also extract data from memory to provide a current status.
  • 11. 11 Support for SNMP DMI can co-exist with SNMP. A single machine can serve as a proxy agent to service an entire LAN segment of DMI machines. When SNMP queries arrive, it can transfer the data from the MIF into the SNMP's MIB (management information base). See CIM, SNMP, WBEM and DMTF. What is the Cisco Discovery Protocol (CDP)? CDP is a Cisco proprietary protocol that runs on all Cisco IOS-enabled devices. It is used to gather information about directly connected neighboring devices. CDP operates at Layer 2 of the OSI model and is media-independent. With CDP, you can tell the hardware type, device identifier, address list, software version, and active interfaces on neighboring Cisco devices. CDP is enabled by default on all Cisco equipment. It uses a nonroutable SNAP frame to communicate between devices. Note: Because CDP is media-independent it can operate over most media types. The only media types CDP cannot operate over are X.25, because it doesn't support SNAP encapsulation, and Frame Relay point-to-multipoint interfaces. What are three reasons to disable CDP? Three reasons to disable CDP are as follows: . To save network bandwidth by not exchanging CDP frames.
  • 12. 12 . If you are connecting to non-Cisco devices. . Security. CDP broadcasts information about the device every 60 seconds. Sniffers and other devices can view these broadcasts to discover information about your network. How do you disable CDP on Cisco routers? Two commands disable CDP on a Cisco router. To disable CDP on the entire device, use the no cdp run global command: RouterB(config)#no cdp run To disable CDP on an interface only, use the no cdp enable interface command: RouterB(config)#int e0 RouterB(config-if)#no cdp enable This disables CDP on Ethernet interface 0. What does the show CDP command display? The show CDP command displays global CDP information about the device. It tells you when the device will send CDP packets and the CDP holdtime: RouterB#show cdp Global CDP information: Sending CDP packets every 60 seconds Sending a holdtime value of 180 seconds Note: For the CCNA test, remember that the default time a device will send out CDP information is 60 seconds and the default holdtime is 180 seconds. On a Cisco router, what does the show cdp neighbors command display?
  • 13. 13 The show cdp neighbors command displays the following: · Device ID (name of the device) · The local interface (local outgoing port) · The holdtime displayed in seconds · The device's capability code (this tells you if the device is a router, switch, or repeater) · Hardware platform of the neighboring device (what type of Cisco device it is and the model) · Port ID of the neighboring device (remote port) RouterB#show cdp neighbors Capability Codes: R - Router, T - Trans Bridge, B - Source Route Bridge S - Switch, H - Host, I - IGMP, r - Repeater Device ID Local Intrfce Holdtme Capability Platform Port ID RouterA Ser 0 146 R 2505 Ser 0 What does the show cdp neighbors detail command display? The show cdp neighbors detail and show cdp entry * commands show the same output. They both display the following: · Device ID (host name) of the remote neighbor · Layer 3 address of the remote device (if the device has more than one Layer 3 address on its interface, only the primary address is shown)
  • 14. 14 · Device platform and capabilities· Local interface and outgoing port ID · Remote device holdtime in seconds · IOS type and version RouterB#show cdp neighbors detail ------------------------- Device ID: RouterA Entry address(es): IP address: 192.168.2.1 Platform: cisco 2505, Capabilities: Router Interface: Serial1, Port ID (outgoing port): Serial1 Holdtime : 164 sec Version :Cisco Internetwork Operating System Software IOS (tm) 2500 Software (C2500-D-L), Version 12.0(13), RELEASE SOFTWARE (fc1)Copyright (c) 1986-2000 by cisco Systems, Inc.Compiled Wed 06-Sep-00 01:08 by Linda What does the show cdp traffic command display? The show cdp traffic command displays information about interface traffic. This includes the number of CDP packets sent and received and CDP errors: RouterB#show cdp traffic CDP counters : Packets output: 105, Input: 103
  • 15. 15 Hdr syntax: 0, Chksum error: 0, Encaps failed: No memory: 0, Invalid packet: 0, Fragmented: 0 What does the show cdp interface command display? The show cdp interface command displays the status of CDP on all interfaces on your device: RouterB#show cdp interface Ethernet0 is up, line protocol is down Encapsulation ARPA Sending CDP packets every 60 seconds Holdtime is 180 seconds Serial0 is up, line protocol is up Encapsulation HDLC Sending CDP packets every 60 seconds Holdtime is 180 seconds Serial1 is up, line protocol is up Encapsulation HDLC Sending CDP packets every 60 seconds Holdtime is 180 seconds What Cisco IOS router command can you use to see a neighbor router's IP address? To see a neighbor router's IP address, you must use the show cdp neighbor detail or show cdp entry * user mode or EXEC command. (This one will probably be on the exam) What IOS command do you use to view the active outbound telnet sessions for the current user on a Cisco router?
  • 16. 16 The show sessions command displays the active outbound telnet sessions from that particular user on your router. RouterA#show sessions Conn Host Address Byte Idle Conn Name * 1 192.168.1.2 192.168.1.2 0 0 192.168.1.2 What key sequence do you use to suspend a Telnet session on a remote system and return to your local router? To suspend a Telnet session, press Ctrl-Shift-6, and then press X. How do you end a remote Telnet session on a Cisco router? To end a Telnet session, use the exit or logout command while you're on the remote device: RouterB>exit [Connection to 192.168.1.2 closed by foreign host] RouterA# Upon using the ping EXEC command, you receive one of the following responses: · . · ! · ? · C · U
  • 17. 17 · I What does each of these responses mean? . = Each period indicates that the network server timed out while waiting for a reply. ! =Each exclamation point indicates the receipt of a reply. ? =Unknown packet type. C =A congestion experienced packet was received. U =A destination unreachable error PDU was received. I = The user interrupted the test. What is the trace EXEC command used for? RouterA#trace 192.168.2.2 Type escape sequence to abort. Tracing the route to 192.168.2.2 1 192.168.2.2 16 msec 16 msec * Note: If trace responds with a * it means the probe timed out. If it responds with a ? it means it received an unknown packet type. What are the two ways in which a Cisco router resolves host names to IP addresses? A Cisco router resolves host names using either a host table on each router or a DNS server. What is the main purpose of RAM on a Cisco router? On most Cisco routers, the IOS is loaded into RAM, as well as the running configuration. It is also used to hold routing tables and packet buffers.
  • 18. 18 What is the function of ROM on a Cisco router? On a Cisco router, ROM is used to start and maintain the router. What is Flash memory used for on a Cisco router? Flash memory is used to store the Cisco IOS software image and, if there is room, multiple configuration files or multiple IOS files. On some routers (the 2500 series), it is also used to run the IOS. What is the function of NVRAM on a Cisco router? Nonvolatile Random-Access Memory (NVRAM) is used to hold the saved router configuration. This configuration is not lost when the router is turned off or reloaded. What is the main purpose of the configuration register on a Cisco router? The configuration register's main purpose is to control how the router boots up. It is a 16-bit software register that by default is set to load the Cisco IOS from Flash memory and to look for and load the startup-config file from NVRAM. What Cisco IOS command would you use to view the current configuration register value? The show version command is used to display the router's current configuration register: RouterA#show version Cisco Internetwork Operating System SoftwareIOS (tm) 2500 Software (C2500-D-L), Version 12.0(13), RELEASE SOFTWARE (fc1)Copyright (c) 1986-2000 by cisco Systems, Inc.Compiled Wed 06-Sep-00 01:08 by lindaImage text-base: 0x030388F8, data-base: 0x00001000 Configuration register is 0x2102 How do you change the configuration register on a Cisco router? To change the configuration register on a Cisco router, use the config-register global command.
  • 19. 19 What Cisco IOS command displays the contents of Flash memory? The show flash command displays the contents of Flash memory. This includes the images stored in Flash memory, the images' names, bytes used in Flash memory, bytes available, and the total amount of Flash memory on your router: RouterA#show flash System flash directory:File Length Name/status 1 6897716 c2500-d-l.120-13.bin[6897780 bytes used, 1490828 available, 8388608 total]8192K bytes of processor board System flash (Read ONLY) What IOS command would you use to copy the running configuration on a router to a TFTP server? To copy the running configuration to a TFTP server, use the copy running-config tftp privileged EXEC command: RouterB#copy run tftp Address or name of remote host []? 192.168.0.2 Destination filename [routerb-confg]? !! 780 bytes copied in 6.900 secs (130 bytes/sec) This gives you a backup of your running config on a TFTP server. How do you erase the router's configuration and bring it back to the factory default? The erase startup-config privileged EXEC command erases your router's configuration, thus bringing it back to its factory defaults: RouterB#erase startup-config
  • 20. 20 Erasing the nvram filesystem will remove all files! Continue? [confirm] [OK]Erase of nvram: complete Note: In order to complete the process, you need to reload the router. An older IOS command that you can use to accomplish the same results is write erase. How do you restore a configuration file from a TFTP server into your Cisco router's RAM? The copy tftp running-config privileged EXEC command merges the saved and running configuration into your router's RAM, so any commands not explicitly change or removed will remain in the running configuration. RouterB#copy tftp running-config Address or name of remote host []? 192.168.0.2 Source filename []? routerb-confg Destination filename [running-config]? Accessing tftp://192.168.0.2/routerb-confg... Loading routerb-confg from 192.168.0.2 (via Ethernet0): ! [OK - 780/1024 bytes] 780 bytes copied in 4.12 secs (195 bytes/sec) RouterB# 01:40:46: %SYS-5-CONFIG: Configured from tftp://192.168.0.2/routerb-confg How do you back up a Cisco router IOS? To back up the current IOS image on your router, use the copy flash tftp privileged EXEC mode command: RouterB#copy flash tftp
  • 21. 21 Source filename [routerb-flash]? flash:c2500-d-l.120-13.bin Address or name of remote host []? 192.168.0.2 Destination filename [c2500-d-l.120-13.bin]? !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!6897716 bytes copied in 90.856 secs (76641 bytes/sec) How do you upgrade or restore the Cisco router IOS? To upgrade or restore the Cisco router IOS, use the copy tftp flash privileged EXEC mode command. How you make a Cisco router a TFTP server? To configure a Cisco router as a TFTP server, use the tftp-server global configuration command. What is the boot sequence of a Cisco router? The boot sequence of a router is as follows: hardware /power on load run bootstrapfind the IOS software load the softwarefind the config (default NVRAM) load the configuration (startup-config) into RAM Run the IOS What can you configure on a router in setup mode? ip addresses
  • 22. 22 routed protocols enable password Important Config Register Notes: 2100 manual boot rommon> 2101 boot from ROM 2102 normal/password recovery 2105 boot system command - config-register NVRAM 2142 bypass NVRAM ctrl-break = ROM monitor mode router(config)#boot system flash ios filename router(config)#boot system tftp filename ip address router(config)#boot system ROM Note the router prompt for boot commands. Copy commands = router# (Used only for educational purpose) Ammad khan