It is possible to respond to slow clients by simply dropping their MDS sessions, but permit them to re-open sessions and permit them to continue talking to OSDs. To enable this mode, set mds_session_blacklist_on_timeout to false on your MDS nodes.

Hello, When connection is lost between kernel client, a few things happen: 1. Caps become stale: Aug 11 11:08:14 admin-cap kernel: [308405.227718] ceph: mds0 caps stale 2. MDS evicts client for being unresponsive: MDS log: 2020-08-11 11:12:08.923 7fd1f45ae700  0 log_channel(cluster) log [WRN] : evicting unresponsive client admin-cap.cf.ha.cyberfusion.cloud:DB0001-cap (144786749), after 300.978 seconds Client log: Aug 11 11:12:11 admin-cap kernel: [308643.051006] ceph: mds0 hung 3. Socket is closed: Aug 11 11:22:57 admin-cap kernel: [309289.192705] libceph: mds0 [fdb7:b01e:7b8e:0:10:10:10:1]:6849 socket closed (con state OPEN) I am not sure whether the kernel client or MDS closes the connection. I think the kernel client does so, because nothing is logged at the MDS side at 11:22:57 4. Connection is reset by MDS: MDS log: 2020-08-11 11:22:58.831 7fd1f9e49700  0 --1- [v2:[fdb7:b01e:7b8e:0:10:10:10:1]:6800/3619156441,v1:[fdb7:b01e:7b8e:0:10:10:10:1]:6849/3619156441] >> v1:[fc00:b6d:cfc:951::7]:0/133007863 conn(0x55bfaf1c2880 0x55c16cb47000 :6849 s=ACCEPTING_WAIT_CONNECT_MSG_AUTH pgs=0 cs=0 l=0).handle_connect_message_2 accept we reset (peer sent cseq 1), sending RESETSESSION Client log: Aug 11 11:22:58 admin-cap kernel: [309290.058222] libceph: mds0 [fdb7:b01e:7b8e:0:10:10:10:1]:6849 connection reset 5. Kernel client reconnects: Aug 11 11:22:58 admin-cap kernel: [309290.058972] ceph: mds0 closed our session Aug 11 11:22:58 admin-cap kernel: [309290.058973] ceph: mds0 reconnect start Aug 11 11:22:58 admin-cap kernel: [309290.069979] ceph: mds0 reconnect denied Aug 11 11:22:58 admin-cap kernel: [309290.069996] ceph: dropping file locks for 000000006a23d9dd 1099625041446 Aug 11 11:22:58 admin-cap kernel: [309290.071135] libceph: mds0 [fdb7:b01e:7b8e:0:10:10:10:1]:6849 socket closed (con state NEGOTIATING) Question: As you can see, there's 10 minutes between losing the connection and the reconnection attempt (11:12:08 - 11:22:58). I could not find any settings related to the period after which reconnection is attempted. I would like to change this value from 10 minutes to something like 1 minute. I also tried searching the Ceph docs for the string '600' (10 minutes), but did not find anything useful. Hope someone can help. Environment details: Client kernel: 4.19.0-10-amd64 Ceph version: ceph version 14.2.9 (bed944f8c45b9c98485e99b70e11bbcec6f6659a) nautilus (stable) Met vriendelijke groeten, William Edwards _______________________________________________ ceph-users mailing list -- ceph-users(a)ceph.io To unsubscribe send an email to ceph-users-leave(a)ceph.io