[CentOS] Desktop Over NFS Home Blocked By Firewalld

Sat Nov 21 03:18:03 UTC 2020
Michael B Allen <ioplex at gmail.com>

On Fri, Nov 20, 2020 at 6:37 PM Gordon Messmer <gordon.messmer at gmail.com> wrote:
> On 11/20/20 1:26 PM, Michael B Allen wrote:
> > Thanks for the inputs but my problem has nothing to do with NFS.
> Do you think that because you saw "krbupdate" in /etc/services?
> The problem you've described is definitely an NFSv3 problem.  The
> connections causing the client to hang are portmap connections. They're
> dynamic, and don't necessarily conform to /etc/services.
> The lesson to learn, here, is that /etc/services maps names to numbers,
> but it does NOT map numbers to names.  Port numbers aren't reserved
> simply because there is a mapping to them in /etc/services.

Hi Gordon,

You're right! My mistake. I removed the Source Port rule and did the
following instead:

  # firewall-cmd --add-service=nfs3 --permanent
  # firewall-cmd --reload

This fixed the hanging issue (and probably other stuff I haven't run into yet).

So even though NFS worked fine just doing the usual file related ops
in a terminal, apparently my client is old enough that it's still
doing NFSv3 whereas CentOS 7 has moved on to NFSv4 and that
incompatibility was responsible for the desktop / libreoffice hanging

Much thanks.