High-availability with corosync and pacemaker

1. Corosync
+
Pacemaker
Corosync
+
Pacemaker
Marian HackMan Marinov <mm@1h.com>

2. ArchitectureArchitecture
Corosync
Pacemaker Pacemaker Pacemaker

3. ArchitectureArchitecture
Corosync
Pacemaker Pacemaker Pacemaker
121.12.12.6

4. ArchitectureArchitecture
Corosync
Pacemaker Pacemaker Pacemaker
121.12.12.6

5. ArchitectureArchitecture
Corosync
Pacemaker Pacemaker Pacemaker
121.12.12.6

6. ArchitectureArchitecture
Corosync
Pacemaker Pacemaker Pacemaker
121.12.12.6

7. ArchitectureArchitecture
Corosync
Pacemaker Pacemaker Pacemaker
121.12.12.6

8. ArchitectureArchitecture
➢ Corosync
➢ A messaging and membership layer
➢ Quorum information (odd number of nodes)
➢ Pacemaker
➢ Cluster Resource Manager
➢ resource-agents

9. ManagementManagement
➢ crmsh
➢ Cluster Resource Manager shell
➢ pcs
➢ Pacemaker configuration system

10. Easy clusterEasy cluster
node tom
node jerry
primitive apache lsb:apache
op monitor interval=2s target-role=Started
primitive ip-10 IPaddr2
params ip=122.12.31.10 cidr_netmask=24 nic=bond0
On tom:
# iptables -t nat -I PREROUTING -j DNAT -d 122.12.31.10
-p tcp --dport 80 --to 10.0.0.1:80
On jerry:
# iptables -t nat -I PREROUTING -j DNAT -d 122.12.31.10
-p tcp --dport 80 --to 10.0.0.2:80

11. Config 1Config 1
node luke attributes standby=off
node leia attributes standby=off
node han attributes standby=off
primitive apache lsb:apache
op monitor interval=2s target-role=Started
primitive bind lsb:named
op monitor interval=5s target-role=Started
primitive cron-migrate lsb:cron-migrate
op monitor interval=15s target-role=Started
meta is-managed=true target-role=Started
primitive ip-10 IPaddr2
params ip=122.12.31.10 cidr_netmask=24 nic=bond0
primitive ip-11 IPaddr2
params ip=122.12.31.11 cidr_netmask=24 nic=bond0

12. Config 2Config 2
clone apache-clone apache meta clone-max=3
clone-node-max=1 globally-unique=false ordered=false
interleave=false target-role=Started
clone bind-clone bind meta clone-max=3
clone-node-max=1 globally-unique=false ordered=false
interleave=false target-role=Started

13. Config 3Config 3
location cli-prefer-cron-migrate cron-migrate
role=Started inf: luke
colocation dont-put-cron-with-webs -100: cron-migrate ( ip-10
ip-11 )
property cib-bootstrap-options:
dc-version=1.1.10-14.el6_5.2-368c726
cluster-infrastructure="classic openais (with plugin)"
expected-quorum-votes=3
stonith-enabled=false
is-managed-default=true
maintenance-mode=false
no-quorum-policy=ignore
rsc_defaults rsc-options:
resource-stickiness=100

14. ConceptsConcepts
➢ Resource = service
➢ clone = multiple instances of a resource
➢ ms = master-slave instances of a resource

15. Types of servicesTypes of services
➢ LSB - linux standard base
➢ can be used for basic stuff
➢ /etc/init.d/resource
➢ OCF - Open Cluster Framework
➢ required for ms resources
➢ /usr/lib/ocf/resource.d/heartbeat

16. LogicLogic
➢ ordering
➢ location constrains
➢ co-location constrains

17. AlternativesAlternatives
➢ Nomad - www.nomadproject.io
➢ VRRP
➢ vrrpd - github.com/fredbcode/Vrrpd
➢ keepalived - www.keepalived.org
All of the above lack the resource agent
scripts and notion for MS and Cloned
resources

18. Thank YouThank You
IRC: irc.freenode.net hackman
ICQ: 7556201
Jabber: hackman@jabber.com
E-Mail: mm@1h.com