On Tue, Mar 26, 2024 at 7:30 PM Yongseok Oh <yongseok.oh@xxxxxxxxxxxx> wrote: > Hi, > > CephFS is provided as a shared file system service in a private cloud > environment of our company, LINE. The number of sessions is approximately > more than 5,000, and session evictions occur several times a day. When > session eviction occurs, the message 'Cannot send after transport endpoint > shutdown' or 'Permission denied' is displayed and file system access is not > possible. Our users are very uncomfortable with this issue. In particular, > there are no special problems such as network connection or CPU usage. When > I access the machine and take a close look, there are no special problems. > After this, users feel the inconvenience of having to perform umount/mount > tasks and run the application again. In a Kubernetes environment, recovery > is a bit more complicated, which causes a lot of frustration. > > I tested that by setting the mds_session_blocklist_on_timeout and > mds_session_blocklist_on_evict options to false and setting > client_reconnect_stale to true on the client side, the file system can be > accessed even if eviction occurs. It seemed like there was no major problem > accessing the file system as the session was still attached. > What I'm curious about is if I turn on the above option, will there be any > other side effects? For example, should I take some action if the integrity > of the file is broken or if there is an issue on the mds side? I am asking > a question because there are no details regarding this in the official > CephFS documentation. > The suggestion you are following is documented here https://docs.ceph.com/en/latest/cephfs/eviction/#advanced-configuring-blocklisting As you mentioned rightly, it doesn't talk about the side effects if any. But that said, it's kind of a workaround even if it works. Do we know the exact reason for session eviction from the logs ? It could be any of these things mentioned here https://docs.ceph.com/en/latest/cephfs/eviction/#automatic-client-eviction > Thank you > > Yongseok > _______________________________________________ > ceph-users mailing list -- ceph-users@xxxxxxx > To unsubscribe send an email to ceph-users-leave@xxxxxxx > > _______________________________________________ ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an email to ceph-users-leave@xxxxxxx
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