Editing Usage of HPC and HA at BITS Pilani (section)

=='''HIGH AVAILABILITY CLUSTER'''==

Two Nodes on HA:

# ibm-39.bits.ac – 172.20.4.39
# ibm-40.bits.ac – 172.20.4.40

Virtual IP of HA : 172.20.4.43

'''How to Fence from one cluster to another manually , Run command from any node'''

 <nowiki># clusvcadm –d nfs</nowiki>

Here nfs is an cluster service

 <nowiki># clusvcadm –e nfs –m `hostname`</nowiki>

How to check status of cluster

 <nowiki># clustat</nowiki>

[[Image:bits-2.png]]

'''Stop manually HA Cluster by:'''

 <nowiki># service cman stop //Simultaneously as root on ibm-39 and ibm-40</nowiki>

 <nowiki># service rgmanager stop //Simultaneously as root on ibm-39 and ibm-40</nowiki>

'''Start manually HA Cluster by:'''

 <nowiki># service cman start //Simultaneously as root on ibm-39 and ibm-40</nowiki>

 <nowiki># service rgmanager start //Simultaneously as root on ibm-39 and ibm-40</nowiki>

Then check the status of cluster by “clustat” command and also ping to 172.20.4.43 that is your virtual ip of cluster.

'''Note :'''

# When first server is out of the network then it fenced to second server and at same time first server has automatically forcefully rebooted 
# Then virtual ip switch to second server.
# When first server has been UP then need to switch cluster manually.
# You have two choices by clusvcadm or restart rgmanager and cman.
# We take here second option i.e. restart rgmanager and cman

'''On Node2 :'''

 <nowiki># service rgmanager stop</nowiki>
 <nowiki># service cman stop</nowiki>

Then Simultaneously on '''Node1 and Node2'''

<nowiki># service cman start</nowiki>
<nowiki># service rgmanager start</nowiki>

And check 
 
clustat