EX4400 Virtual Chassis do not form and you find out that the vc-ports, and FPC are missing even though they are properly configured and inserted. 

• Juniper Networks EX4400 Series virtual chassis is not forming and you notice vc-ports are missing. 
• The VC ports light would not show as light up.
• "show chassis hardware" would not display output about FPCs.
• "show chassis fpc no-forwarding" will display slot as empty

When you check for vc-ports status the output is empty as follow:

root> show virtual-chassis vc-port

fpc0:

--------------------------------------------------------------------------

This could mean that the ports are currently working as network ports and need to be converted to vc-ports by running the following commands:

>request virtual-chassis mode disable network-port

>request system reboot

After the device comes up you can check again for the vc-ports status:

root> show virtual-chassis vc-port

fpc0:

--------------------------------------------------------------------------

Interface  Type       Trunk Status    Speed    Neighbor

or               ID         (mbps)    ID Interface

PIC / Port

1/0     Configured     -1  Down     100000

1/1     Configured     -1  Down     100000

In our case, after configuring the ports to vc-ports the issue remained, reseat the VC-ports, reconfigured them and reboot the VC did not fix the issue. 

root@> show chassis fpc no-forwarding

                     Temp  CPU Utilization (%)   CPU Utilization (%)  Memory    Utilization (%)
Slot State            (C)  Total  Interrupt      1min   5min   15min  DRAM (MB) Heap     Buffer
  0  Empty
  1  Empty
  2  Empty
  3  Empty
  4  Empty
  5  Empty
  6  Empty
  7  Empty
  8  Empty
  9  Empty

This output does not display information about the connected FPC and is showing as empty even though the FPC is properly connected, and was reseated and rebooted. Since all efforts to recover functionality failed RMA was required for defective FPC0. 

05-10-2023 KB created