(edfa-troubleshooting)=

# Troubleshooting

> _TODO: confirm and extend._

| Symptom | Check |
| -- | -- |
| STATUS LED flashing or red | Run `velia-list-alarms`; check both power supplies and the fans |
| No IP address | Check the cable on eth0; check the DHCP server; use the console and `ifconfig` |
| Low or zero gain | Pump enabled? Pump current set? Input power in range? Connectors clean? |