# Use of Status LEDs to Monitor the High Availability States of Line Modules

You can determine the redundancy state of line modules and SRP modules by examining their status LEDs. The LED on the line module denotes the state of the line module. In addition, if you issue the show version command, the state field for the slot that contains the redundant line module indicates standby. The following are the functions of the LEDs for the different states of the line modules in a high availability pair:

- OK LED—This LED is turned off while the secondary line module is switching over
- ONLINE LED—There is no difference in the method of illumination of this LED, regardless of whether line module high availability is enabled.
- REDUNDANT LED—This LED is turned on for the secondary line module and is not illuminated for the primary line module.

#### Related Documentation

- Monitoring the Redundancy Status of Line Modules in a Specific Slot
- Monitoring the Redundancy History of Line Modules in a Specific Slot