ServerNet Cluster 6780 Planning and Installation Guide (G06.29+, H06.06+, J06.03+)
Troubleshooting
ServerNet Cluster 6780 Planning and Installation Guide—527301-008
10-3
Yellow Fault LED on a Switch Is Lit
Yellow Fault LED on a Switch Is Lit 
A yellow fault LED that is lit but not blinking indicates an error. The CRU might be 
incorrectly seated in the slot, or the CRU might have been inserted too slowly.
1. Wait a few minutes to see if the fault LED clears. The fault LED is normally on 
while a CRU is undergoing a power-on self test (POST).
2. If the problem continues, completely remove the CRU from its slot. 
3. For power supplies, wait 5 seconds before reinserting the CRU. 
4. Reinsert the CRU into its slot.
Yellow Fault LED on a Switch Is Blinking 
A blinking yellow Fault LED does not indicate an error. You can use OSM or SCF to 
blink this LED on a CRU to help you locate that CRU. To turn the blinking off, refer to 
the ServerNet Cluster 6780 Operations Guide.
An OSM Alarm on the External Fabric Is Generated 
An OSM alarm on the external fabric indicates a problem between a node and the 
switch that the node is connected to. The problem might be in any of these 
components:
•
A 6780 switch, switch PIC, or switch port to which the node is connected
•
SANMAN or SNETMON processes
•
A remote node
•
Components in the node used to connect to the switch. In NonStop S-series 
servers, there might be a problem with these components:
°
The MSEB in slot 51 or 52 of the group 01 system enclosure of the local node
°
The PIC in port 6 of the MSEB in slot 51 or 52 of the group 01 system 
enclosure of the local node
°
The cable from the PIC in port 6 of the MSEB in slot 51 or 52 of the group 01 
system enclosure to the switch










