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Creating a RHEL cluster with Virtual IP using CMAN and Pacemaker.

Creating a two-node RHEL cluster with Virtual IP using CMAN and Pacemaker.

Important Links : 
http://blog.mattbrock.co.uk/creating-a-two-node-centos-6-cluster-with-floating-ip-using-cman-and-pacemaker/
http://clusterlabs.org/quickstart-redhat-6.html

Configuring Repo on RHEL 6.6

[root@waepprrkhe001 ~]# cat /etc/yum.repos.d/centos.repo
[centos-6-base]
name=CentOS-$releasever - Base
mirrorlist=http://mirrorlist.centos.org/?release=6&arch=x86_64&repo=os
baseurl=http://mirror.centos.org/centos/6/os/x86_64/
enabled=1
gpgkey=http://mirror.centos.org/centos/6/os/x86_64/RPM-GPG-KEY-CentOS-6
[root@waepprrkhe001 ~]#

Installation and initial configuration

Install the required packages on both machines:
yum install pacemaker cman pcs ccs resource-agents
Set up and configure the cluster on the primary machine, changing vipcluster, primary.server.com and secondary.server.com as needed:
ccs -f /etc/cluster/cluster.conf --createcluster vipcluster
ccs -f /etc/cluster/cluster.conf --addnode primary.server.com
ccs -f /etc/cluster/cluster.conf --addnode secondary.server.com
ccs -f /etc/cluster/cluster.conf --addfencedev pcmk agent=fence_pcmk
ccs -f /etc/cluster/cluster.conf --addmethod pcmk-redirect primary.server.com
ccs -f /etc/cluster/cluster.conf --addmethod pcmk-redirect secondary.server.com
ccs -f /etc/cluster/cluster.conf --addfenceinst pcmk primary.server.com pcmk-redirect port=primary.server.com
ccs -f /etc/cluster/cluster.conf --addfenceinst pcmk secondary.server.com pcmk-redirect port=secondary.server.com
Copy /etc/cluster/cluster.conf from the primary server to secondary server in cluster.
It’s necessary to turn off quorum checking, so do this on both machines:
echo "CMAN_QUORUM_TIMEOUT=0" >> /etc/sysconfig/cman

Start the services

Start up the services on both servers. 
service cman start
service pacemaker start
Make sure both services can be reboot:
chkconfig cman on
chkconfig pacemaker on

Configure and create floating IP

Configure the cluster on the primary server.
pcs property set stonith-enabled=false
pcs property set no-quorum-policy=ignore
Create the Virtual IP on the primary server. This VIP will be assigned between the 2 servers.
If primary goes down, then this ip is assigned to the secondary server. 
pcs resource create vipbalancerip ocf:heartbeat:IPaddr2 ip=192.168.0.100 cidr_netmask=32 op monitor interval=30s
pcs constraint location vipbalancerip prefers primary.server.com=INFINITY

Cluster administration

To monitor the status of the cluster:
pcs status
Here is the output from primary
[root@waepprrkhe001 ~]# pcs status
Cluster name: vipcluster
Last updated: Mon Sep 28 20:53:57 2015
Last change: Mon Sep 28 19:52:47 2015
Stack: cman
Current DC: primary.server.com - partition with quorum
Version: 1.1.11-97629de
2 Nodes configured
1 Resources configured


Online: [ primary.server.com secondary.server.com ]

Full list of resources:

 livefrontendIP0        (ocf::heartbeat:IPaddr2):       Started primary.server.com

[root@waepprrkhe001 ~]#
To show the full cluster configuration:
pcs config
Here is the output from primary
[root@waepprrkhe001 ~]# pcs config
Cluster Name: vipcluster
Corosync Nodes:
 primary.server.com secondary.server.com
Pacemaker Nodes:
 primary.server.com secondary.server.com

Resources:
 Resource: livefrontendIP0 (class=ocf provider=heartbeat type=IPaddr2)
  Attributes: ip=192.168.0.100 cidr_netmask=32
  Operations: start interval=0s timeout=20s (livefrontendIP0-start-interval-0s)
              stop interval=0s timeout=20s (livefrontendIP0-stop-interval-0s)
              monitor interval=30s (livefrontendIP0-monitor-interval-30s)

Stonith Devices:
Fencing Levels:

Location Constraints:
  Resource: livefrontendIP0
    Enabled on: primary.server.com (score:INFINITY) (id:location-livefrontendIP0-primary.server.com-INFINITY)
Ordering Constraints:
Colocation Constraints:

Resources Defaults:
 No defaults set
Operations Defaults:
 No defaults set

Cluster Properties:
 cluster-infrastructure: cman
 dc-version: 1.1.11-97629de
 no-quorum-policy: ignore
 stonith-enabled: false
[root@waepprrkhe001 ~]#

Failover testing.

Shutdown secondary server.
[root@waepprrkhe001 ~]# pcs status
Cluster name: vipcluster
Last updated: Mon Sep 28 20:08:00 2015
Last change: Mon Sep 28 19:52:47 2015
Stack: cman
Current DC: primary.server.com - partition WITHOUT quorum
Version: 1.1.11-97629de
2 Nodes configured
1 Resources configured


Online: [ primary.server.com ]
OFFLINE: [ secondary.server.com ]

Full list of resources:

 livefrontendIP0        (ocf::heartbeat:IPaddr2):       Started primary.server.com
Shutdown primary server. 
[root@waepprrkhe002 ~]# pcs status
Cluster name: vipcluster
Last updated: Mon Sep 28 20:05:30 2015
Last change: Mon Sep 28 19:52:47 2015
Stack: cman
Current DC: secondary.server.com - partition WITHOUT quorum
Version: 1.1.11-97629de
2 Nodes configured
1 Resources configured


Online: [ secondary.server.com ]
OFFLINE: [ primary.server.com ]

Full list of resources:

 livefrontendIP0        (ocf::heartbeat:IPaddr2):       Started secondary.server.com
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