I am facing a strange problem. I have installed RH 7.2 and it was working fine. I was able to telnet, SSH properly. Now suddenly (!) if I try to telnet by any user it gives an error message:
Last Login:.....
/home/user1: No Home Directory!

and it disconnects.

Also when I am logged in as root (using SSH) and I try to do a

su - user1

I get the error:
su: cannot run /bin/bash: Permission denied


Any ideas!!

I am stuck. Please help.

Thanks in advance.....
... Atul

Plz do *not* use telnet. It doesn't use encryption so any data sent can be sniffed from the wire to grab your passwords, commands, everything.
Best is to remove telnet and telnetd (the telnet daemon) from your system. Use SSH instead.
Plz do *not* login as *root* with SSH. Login as any regular user and then use sudo to su to root.
It's the proper way to do it.
If you must login as root dont forget to set allowing rootlogins in sshd.conf.
Btw, you *did* upgrade your sshd to the last version w/o vulnerabilities?..

By the errors you are getting it looks like you either have permissions set wrong or you are missing a few things.

When it says permission denied to /bin/bash then most likely you gotta make sure that user has write and execute rights in the /bin directory and for the bash file.
The same for not finding the home directories. Either it's not present or the permissions are not set properly. The user has to have x rights all the way down to the root dir. The /home directory usually should have the permissions rwxr-x--x owner=root group=adm.

If you personally haven't changed any of these things then I'd start looking around for signs of breakins. Because they don't change by themselves.