[NFS-Ganesha-Support] Re: NFSv3 NLM service conflict with linux kernel client

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(a)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-n... > < https://ganltc.github.io/problem-determination-guide-for-spectrum-scale-n... > > > > > < https://ganltc.github.io/problem-determination-guide-for-spectrum-scale-n... > < https://ganltc.github.io/problem-determination-guide-for-spectrum-scale-n... >> > > > §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(a)lists.nfs-ganesha.org > <mailto:support@lists.nfs-ganesha.org> > To unsubscribe send an email to > support-leave(a)lists.nfs-ganesha.org > <mailto:support-leave@lists.nfs-ganesha.org> >