On Monday, August 30th, 2021 at 12:10 PM, Luciano Mannucci <luciano@???> wrote:

> Hello,
> I have two Beowulf systems that should be identical. If I issue "df"
> one does report among mounted filesystems a /run/user/xxx, where xxx
> is the id number of the user I am connected with (via ssh) and the
> other doesn't. As uname -a they both report:
> Linux mil-dbs66 4.19.0-14-amd64 #1 SMP Debian 4.19.171-2 (2021-01-30) x86_64 GNU/Linux
> What have I done wrong, and on which one of the two machines?
Not necessarily anything wrong, other than the two machines are not identical.

/run/user/xxx is used by session management (and in some corner cases its absence can break dpkg scripts).

You could list all the processes on both machines and then diff them.
Quick and dirty (and untested :)

local_host# ps -e | awk '{print $4}' | sort | uniq >/tmp/catch0
local_host# ssh remote_machine 'ps -e' | awk '{print $4}' | sort | uniq >/tmp/catch1
local_host# diff /tmp/catch0 /tmp/catch1


> Thanks in advance,
> Luciano.