On Mon, Apr 5, 2021 at 11:55 AM Sage Weil <sage@newdream.net> wrote:
>
> On Mon, Apr 5, 2021 at 1:33 PM Jeff Layton <jlayton@redhat.com> wrote:
> >
> > On Thu, 2021-04-01 at 11:04 +0200, Dan van der Ster wrote:
> > > If one kernel mounts the
> > > same cephfs several times (with different prefixes), we observed that
> > > this is a unique client session. But does the ceph module globally
> > > share a single copy of cluster metadata, e.g. osdmaps, or is that all
> > > duplicated per session?
> > >
> >
> > One copy per-cluster client, which should generally be shared between
> > mounts to the same cluster, provided that you're using similar-enough
> > mount options for the kernel to do that.
>
> I suspect the problem is that if these are coming from mgr/volumes,
> then each mount has a unique cephx user (and a client cap that locks
> them into the exported directory), which means that the client
> instances can't be shared.

This is how it works for Manila but not CSI. As I recall, a single
cephx user credential is used for all mounts by CSI.

+Travis Nielsen  / +Humble Chirammal

--
Patrick Donnelly, Ph.D.
He / Him / His
Principal Software Engineer
Red Hat Sunnyvale, CA
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