NFS nolock option

Maximum availability architecture recommends clustered deployment of middleware components and for the admin server to be positioned on a NFS mount which can switch between the clustered nodes.

I implemented one such architecture and encountered the NFS Nolock problem recently. Here is the error and a safe resolution.

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While attmpting to startup nodemanager using wlst, the node manager starts up fine. however, the folowing error is seen. if this error is ignored, we could landup wasting a lot of time troubleshoting further.

Jul 16, 2015 11:34:35 PM weblogic.nodemanager.server.NMServer initDomains
WARNING: Configuration error while reading domain directory: /mnt/oracle/****/****/**_Domain
java.io.IOException: No locks available
     at sun.nio.ch.FileChannelImpl.lock0(Native Method)
     at sun.nio.ch.FileChannelImpl.lock(FileChannelImpl.java:832)
     at weblogic.nodemanager.server.UserInfo.load(UserInfo.java:149)
     at weblogic.nodemanager.server.DomainManager.loadUserInfo(DomainManager.java:139)
     at weblogic.nodemanager.server.DomainManager.initialize(DomainManager.java:90)
     at weblogic.nodemanager.server.DomainManager.(DomainManager.java:60)
     at weblogic.nodemanager.server.NMServer.initDomains(NMServer.java:225)
     at weblogic.nodemanager.server.NMServer.start(NMServer.java:197)
     at weblogic.nodemanager.server.NMServer.main(NMServer.java:382)
     at weblogic.NodeManager.main(NodeManager.java:31)

Jul 16, 2015 11:34:35 PM weblogic.nodemanager.server.Listener run
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While starting Admin server, using wlst, the following error will be seen  :

There are 1 nested errors:
weblogic.management.ManagementException: Unable to obtain lock on /user_projects/domains/biadm10_bifoundation_domain/servers/AdminServer/tmp/AdminServer.lok. Server may already be running
 
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90% of the problem is resolved when you have determined that the problem is due to NFS and not due to the non availability or availability of the lck file :) and the remaining 10% is to make a small edit on  /etc/fstab

Note (Doc ID 1635553.1) has the solution explained. I had the problem resolved by enable the nolock mount option.

nolock,vers=3,tcp,timeo=300
nolock,vers=3,tcp,timeo=300


Cheers :)
Arun