This article explains about an issue where the Routing Engine (RE) does not power up after insertion into a Control Board (CB), even though the CB appears online. This behavior is typically caused by the CB not delivering the required 12.0V power to the RE, preventing it from initializing or showing any LED activity.
1) CB shows as Online in the below output:
> show chassis environment cb CB 0 status: State Online Master Temperature 36 degrees C / 96 degrees F CB 1 status: State Online Standby Temperature 36 degrees C / 96 degrees F
> show chassis environment cb
CB 0 status:
State Online Master
Temperature 36 degrees C / 96 degrees F
CB 1 status:
State Online Standby
2) CLI output shows 0 mV on the 12.0 V RE line, indicating missing power supply to the RE:
> show chassis environment cb | match "CB|V RE" CB 0 status: 5.0 V RE 4995 mV 12.0 V RE 0 mV CB 1 status: 5.0 V RE 4962 mV 12.0 V RE 11891 mV
> show chassis environment cb | match "CB|V RE"
5.0 V RE 4995 mV
12.0 V RE 0 mV
5.0 V RE 4962 mV
12.0 V RE 11891 mV
3) The RE inserted into the CB does not show any LED activity, no blinking or solid LEDs - indicating it is inaccessible and not booting up. Only the CB LEDs show as online (green).
CB0 voltage for 12.0 V RE is shown as 0 mV. This indicates that the CB is not delivering the correct voltage to the RE, which prevents the RE from powering up.
To isolate and address the issue, perform the following steps during a maintenance window:
1) Verify Power Capacity:
Ensure the chassis has sufficient power budget to support all installed components.
2) Physically Inspect the CB and Slot:
Remove the affected CB from the chassis.
Check for any visible burn marks, bent pins, or debris on both the CB and chassis slot.
3) Reseat the CB:
Re-insert the same CB into its original slot.
Check the voltage readings again.
3) Test in Alternate Slot:
Insert the affected CB into a different CB slot in the chassis.
If the issue follows the CB (i.e., 12.0 V RE remains 0 mV), it likely points to a hardware fault with the CB.
If the same behavior persists when the CB is inserted into another slot, it may indicate a hardware issue with the CB that requires further investigation, please reach out to Juniper Technical Support Centre.