DS5000 Won't Accept Any Login Except Root

[Joshua Yeidel]

We have had similar occurances twice:  a DS5000 running Ultrix 4.1
suddenly begins refusing logins from any userid except root.
On investigation, we find that permissions for a high-level
directory (in one case, /, in another, /usr/users) have been
changed such that users can't access something vital (in the
first case, /bin/csh, in the other, their home directories).
Has any one seen anything like this before?  Any clues as to
the cause (We DO know how to fix it once it's gone wrong, but
we'd like to know what might be doing this...)

---------------original message-------------------------------
I found the problem ... it was permissions alright ... somehow the permissions
on the directory that holds all the userid ids (on the dial machine they are
in '/user/users') had gotten changed to rwx------ and the passwd file says
the root directory for a user is at /user/users, but they then didn't have
the permissions to get to it ...

I did three things yesterday which I can identify as the *possible* cause:

1) I copied /bin/lp into /user/users/ftp/bin/ls

2) I generated a new userid, 'ftp' and had the adduser command generate a
   default $HOME directory for it.

Since identifying the problem and fixing it this morning, I have repeated the
above steps (i blew it all off yesterday when we started having problems).
The problem has not be repeatable.

3) From a userid, 'swanv', I ftped a remote file, uncompressed and untarred
   it in a directory /user/users/swanv/swb.

At no time was I monkeying with the directory '/user/users'. I was monkeying
with directories one level down, however.

It would be nice to be able to identify the problem, so that it could be
avoided in the future, but I am at a loss to currently explain it.