[gpfsug-discuss] -o syncnfs has no effect?

[Billich Heinrich Rainer (PSI)]

Hello,

I try to mount a fs with "-o syncnfs" as we'll export it with CES/Protocols. But I never see the mount option displayed when I do

 # mount | grep fs-name

This is a remote cluster mount, we'll run the Protocol nodes in  a separate cluster. On the home cluster I see the option 'nfssync' in the output of 'mount'.

My conclusion is that the mount option "syncnfs" has no effect on remote cluster mounts. Which seems a bit strange?

Please can someone clarify on this? What is the impact on protocol nodes exporting remote cluster mounts? Is there any chance of data corruption? Or are some mount options implicitely inherited from the home cluster? I've read 'syncnfs' is default on Linux, but I would like to know for sure.

Funny enough I can pass arbitrary options with 

  # mmmount <fs-name> -o some-garbage

which are silently ignored.

 I did 'mmchfs -o syncnfs' on the home cluster and the syncnfs option is present in /etc/fstab on the remote cluster. I did not remount on all nodes __

Thank you, I'll appreciate any hints or replies.

Heiner

Versions:
Remote cluster 5.0.1 on RHEL7.4  (imounts the fs and runs protocol nodes)
Home cluster 4.2.3-8 on RHEL6  (export the fs, owns the storage)
Filesystem: 17.00 (4.2.3.0)
All Linux x86_64 with Spectrum Scale Standard Edition
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Paul Scherrer Institut
Science IT
Heiner Billich
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CH 5232  Villigen PSI
056 310 36 02
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