So I had a new developer working on a new VM with RHEL on it and they typod a chmod command and accidentally executed chmod -r 777 /* via sudo and it seems to have messed something up. We can't login remotely, the GUI on the console won't seem to take anyone to a desktop, it just keeps coming back to the login screen. I can't even choose a console login from the GUI login prompt, as it bounces back to the GUI login screen after a minute or so.

I have not taken it down to single user mode yet as I thought I would get some suggestions on how to proceed and potential damage caused. It looks like chmod command has some protection built in when doing recursive actions against / but obviously something is still messed up.

Its impossible (or very close to it) to restore all the files and directories to their original settings.

There's just one thing you can do: Restore the environment from a valid source. I hope you made snapshots and/or system and data backups.

Considering the OP refers to a VM, Id think the best and fastest way to recover is to restore from a VM backup.

More importantly, that brings the question: how often are you backing up your machines?

One of the advantage about VM's is how easy you can backup/restore if something goes wrong...

If you can get it down to single user mode in cli mode you could try http://www.cyberciti.biz/tips/reset-...ermission.html

I was able to get it into single user mode, but given the extend of the repairs (over 900 individual packages) and the time involved vs rebuilding the server I have proceeded to rebuild the server. Once its rebuild I will make a snapshot.. which I had not done. Since these are sandbox VM's we were not actively making snapshots but I think that will change soon. Thanks for your help!

One of our lead developers had a full sudo access to our main DB server- and he ran the 'chmod -r 777 /' command. As you can probably expect, nothing was working. This was a production database- and we needed it to be back as soon as possible.

These are the first steps to do:
http://unix.stackexchange.com/questi...d-777-problems

Next, restores all permissions as it was when the original RPMs were installed. Note that this can be dangerous- as sometimes it is necessary to change permissions for some applications to function.
Next step fix problems due to the previous steps. And finally fix permissions for all everything else manually.