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 GPG: 19F28A586F808C2402351B93C3301A3E258DD79D