# Status LEDs

Upon initial power-up, the components of the router run boot code, go through a series of self diagnostic tests, and synchronize with each other.

When the tests are complete, use the LEDs on each module to determine the status of the router. Observe the line module and SRP module LEDs in the front, and the I/O line module and SRP I/O module LEDs in the rear.

See Troubleshooting for information on the system's LEDs.