How to return terminal prompt to default?

exit

http://reviews.cnet.com/8301-13727_7-10399809-263.html

System Preferences->Sharing->Computer Name.

Create a new admin user account, log into it, and see if the problem persists.

If you worked your way through the above trouble shooting link, ex delete plist etc

then I would try reboot computer to single-user mode (root), and run

fsck -fy

If leroydouglas's tip doesn't do the trick, then I suspect system-wide muck up. Reinstall Lion.

There is nothing particularly wrong with your disk, your Mac computer, configuration nor any other aspect of the system.

The default shell prompt is based of your hostname, and you're currently acquiring your hostname off your ISP's or some other local DNS set-up. Quite possibly from something your (somewhat flakey?) router is dredging up from somewhere.

If you want to customize your terminal prompt (which is the easiest way to get exactly what you want), then set the PS1 symbol in your bash login procedure, exit the session, and start another session.

Details on customizing your bash shell prompt are available here, among other places.

Fixing your router or your local DNS responses (if that DNS is something you have control over) is another and different discussion; you're probably not running DNS services for your LAN, but there may well be other issues with your LAN (and around why you've been resetting the configuration, etc).

MrHoffman is 100% correct. Disk Utility repair permissions, verify (or even repair) have absolutely nothing to do with the prompt you are getting.

And reinstalling Mac OS X will change nothing, as the problem, as MrHoffman explained, has nothing to do with your Mac. It is your router and/or your ISP.

The bash shell always does a reverse DNS lookup on your Mac's IP address to get your computer name. The Mac's DNS lookup service does not get a result from the DNS servers, it will use your computer name as specified in System Preferences -> Sharing. In your case, prior to restarting your cable modem, the DNS lookup did not return anything, so your sharing computer name was used. After the cable modem restart, the DNS lookup started returning a result so bash used that information.

Chances are it is a lot more work than it is worth trying to get the DNS lookup to stop returning a value, so it is easier to just change your PS1 shell variable and get on with life.

You could even use the following to always get your sharing computer name

PS1='$(networksetup -getcomputername):\W \u\$ '

bacause .bashrc is ONLY excuted when starting a sub-shell. It is NOT execute when starting a login shell.

bash when run as a login shell will look for one of the following initialization scripts and use the first one it sees:

.bash_profile

.bash_login

.profile

Other bourne shell variations will also use .profile if they do not fine their personalized flavor of initialization script.