On Fri 2021-07-09 (09:23), Forza wrote:

quoted

In consequence many cronjobs and montoring tools will fail :-(

quoted

You can eliminate the problems by exporting and mounting single
subvolumes only 

This is not possible at our site, we use rotating snapshots created by a
cronjob.

Have you tried using the fsid= export option in /etc/exports? 

I have testet it with localhost:

root@tsmsrvj:/# grep localhost /etc/exports 
/data/fex       localhost(rw,async,no_subtree_check,no_root_squash,fsid=20000001)

root@tsmsrvj:/# mount -v localhost:/data/fex /nfs/localhost/fex
mount.nfs: timeout set for Fri Jul  9 09:32:55 2021
mount.nfs: trying text-based options 'vers=4.2,addr=127.0.0.1,clientaddr=127.0.0.1'

root@tsmsrvj:/# mount | grep localhost
localhost:/data/fex on /nfs/localhost/fex type nfs4 (rw,relatime,vers=4.2,rsize=1048576,wsize=1048576,namlen=255,hard,proto=tcp,timeo=600,retrans=2,sec=sys,clientaddr=127.0.0.1,local_lock=none,addr=127.0.0.1)

root@tsmsrvj:/# du -s /nfs/localhost/fex
du: WARNING: Circular directory structure.
This almost certainly means that you have a corrupted file system.
NOTIFY YOUR SYSTEM MANAGER.
The following directory is part of the cycle:
  /nfs/localhost/fex/spool


-- 
Ullrich Horlacher              Server und Virtualisierung
Rechenzentrum TIK         
Universitaet Stuttgart         E-Mail: horlacher@tik.uni-stuttgart.de
Allmandring 30a                Tel:    ++49-711-68565868
70569 Stuttgart (Germany)      WWW:    http://www.tik.uni-stuttgart.de/
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