On 10/26/21 7:02 AM, Olivier Garaud wrote:
> Thanks for sharing this.
>
You're welcome. I've been thinking about this problem for many years...

Frank


> On Tue, Oct 26, 2021 at 3:35 PM Frank Filz <ffilz@redhat.com
> <mailto:ffilz@redhat.com>> wrote:
>
>     On 10/26/21 2:52 AM, Olivier Garaud via Support wrote:
>     > Hi,
>     >
>     > Do you know if there is a workaround to the NLM problem we can
>     > experience when a client is running on the same host as Ganesha ?
>     >
>     > The linux kernel lock manager registers NLM to the portmapper
>     > overriding the registration done by ganesha.
>     > A more complete description of the problem can be found here:
>     >
>     https://ganltc.github.io/problem-determination-guide-for-spectrum-scale-nfs-ganesha.html
>     <https://ganltc.github.io/problem-determination-guide-for-spectrum-scale-nfs-ganesha.html>
>
>     >
>     <https://ganltc.github.io/problem-determination-guide-for-spectrum-scale-nfs-ganesha.html
>     <https://ganltc.github.io/problem-determination-guide-for-spectrum-scale-nfs-ganesha.html>>
>
>     > §NFS client or application hang due to NLM locks.
>     >
>
>     There is no solution to this. The fact that an NLM client MUST
>     ALSO be
>     an NLM server, and port mapper/rpcbind only allows a single
>     registration
>     for a given RPC program/protocol leaves us no option.
>
>
>     Even replacing rpcbind with something built into Ganesha,
>     something I've
>     considered to allow single node NLM testing, would have very limited
>     capability. It could work in the test environment, because Ganesha
>     would
>     never make portmapper calls, it would just check what the kernel
>     "registration" was and use that to reply to the kernel client,
>     while the
>     kernel client would make portmapper calls which Ganesha would
>     respond to
>     with it's NLM port. Externally, it could only work if you configured
>     remote addresses as either Ganesha clients or as NFS servers
>     (actually
>     you COULD have both kernel NFS server AND Ganesha NFS server this
>     way -
>     the remote addresses configured as NFS servers could also be
>     kernel NFS
>     server clients since the two lockds are allowed to talk to each
>     other.
>     While I have long dreamed of this, the practical use is limited so I
>     have never put the effort in.
>
>
>     Frank
>     _______________________________________________
>     Support mailing list -- support@lists.nfs-ganesha.org
>     <mailto:support@lists.nfs-ganesha.org>
>     To unsubscribe send an email to
>     support-leave@lists.nfs-ganesha.org
>     <mailto:support-leave@lists.nfs-ganesha.org>
>