Follow these instructions to login to your
WRT54GS v2.1 Router.
Connect router cable to your Laptop or Computer. Alternatively use your wireless network.
Recommendation - It's best to use a wired connection while setting up the WRT54GS v2.1 router. This avoids the risk of suddenly being logged off when saving your changes.
Open your web browser of choice and type IP address of your WRT54GS v2.1 router in the address bar. You can find the ip address on the back of your router.
Now enter the default username and password of your router by accessing the admin panel. If you don't have your username and password, you can try one of the default passwords for WRT54GS v2.1 routers.
If you can’t log in to your router, then you are probably entering the wrong username or password. Remember to make a note of both after you've changed them.