On 25/11/2020 22:51, Richard Kimberly Heck wrote:

I can mount fine. The problem is that various programs (LyX, LibreOffice) freeze when attempting to open files on those filesystems. In LyX, I was able to trace the problem to a call to lockd, which never returns. So it seems there is some problem with file locking, which it was suggested involved some firewall problem. Which it does, since disabling the firewall on the server solves the problem. (There's no firewall on the client.)

OK, sorry, I was only thinking about the initial post.

I tested and found some problems opening a file with LibreOffice in "edit" mode when using NFS-v3.
It would only open "read only".  Get a message from lockd that user is "unknown".  Too early in my
AM to track this down.  It maybe related to idmapd.  Will see if I can find the cause later today.

However, I had no problems when using NFS-v4.  Can open, edit, and save documents.

Can you switch to mounting NFS-v4?

FWIW, I did change the fstab entry to...

[2001:b030:112f:2::41]:/home/egreshko  /mnt nfs rw,soft,fg  0 0
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