What is the default username and password for OpenWRT.

There isn't one.

There has to be one. How else would you log on to your router after you push the reset button on the back of your linksys router.

try telnet

Default user is ROOT. Password is set by you using the PASSWD command first time you connect (via telnet), after flashing the router with openwrt.

thanks to all. I was able to remember my old user name and password and was able to log on. Apparently when you push the reset button on the back the username and password is not reset.  I have now flashed back to linksys firmware like I wanted.

Buffalo WZR-HP-G450H

I have openwrt the new version on it. The webui will not come up.  I can get to the login prompt on ssh but it asks for a pw but nothing works.  I tried what is was and I guess after I try resetting it to fix UI the password was changed or something? if I could get into the ssh maybe I can fix the UI

http://wiki.openwrt.org/doc/howto/generic.failsafe
states that you should telnet into the router after using failsafe

Yes, I just found out how to get into it. Now trying to get why the UI won't come up. I am running LUCi but seems bad gateway is all I get.

I even tried just reinstall but seems from SSH that does not change anything back to brand new install so it is broken still
Going to fool with it some more each night. really hope get this running
I had to work on getting the thing to even connect on lan to internet via ssh so I could pkg install .. but that has been done after I manually downloaded using my pc and transferred the files to the router then installed from there.

I got it going finally.. I tftp gargoyle on it.. worked and then I tftp the tftp sysupgrade version to the router.. now I have it working again. It broke last time just by changing the lan IP

I think when you use the "reset button" may not work.