Very Computer

I have the following problem:
in a DECstation running Ultrix 4.3 whose administration I recently started,
"su" stopped working. I can "su" to my username and everything goes fine, but
when I "su" (or "su -", or "su -f") to become root, the "su" process becames
idle ("ps" reports idle with raised priority, "I<" ).

After a shutdown everything was OK again, but only for some time (overnight).
I have checked the integrity of the "su" binary and a bunch of other possible
problems but haven't found the answer yet...

Please help me! What could be wrong with this system ?!?

Thank you very much for your answers (if you prefer to answer by email, I'll
post a summary of your suggestions afterwards).

Nuno.

--------------------------------------------------------------------------------
     Nuno Ferreira dos Santos     |  Grupo de Sistemas e Servicos Telematicos

   Telf. : 3100 305   Sala: 436   |      Sistemas e Computadores (Lisboa)
--------------------------------------------------------------------------------

: "su" stopped working. I can "su" to my username and everything goes fine, but
: when I "su" (or "su -", or "su -f") to become root, the "su" process becames

1. the permissions ok? -rws--x--x
2. the user from which you want to become su root has to be in the group
   0 (system)

Juergen

2) Check that your account is in group 0, ie. wheel.

--