EX4200 VC ports not forwarding after unexpected shutdown

Hello everybody,

I've a big problem on a mixed EX4200 - EX4550 VC. In brief, after an unexpected shutdown due to power problems of two members of the VC (master and backup, both EX4200 at the same location) the backup EX4200 (FPC1) is not forwarding anymore packets from its ports, and also a linecard EX4200 (FPC2) is not forwarding anymore on some ports.

After the shutdown I restarted the two machines sequentially (first the master, then the backup). I tried to restart the backup several times but the result is the same.

I also noticed that the VC web interface does not respond (timeout) when trying to list aggregated links. However, the CLI seems to work normally.

In the following some information about the virtual chassis:

> show virtual-chassis

Virtual Chassis ID: dbf4.4d23.6f06
Virtual Chassis Mode: Mixed
Mstr Mixed Neighbor List
Member ID Status Serial No Model prio Role Mode ID Interface
0 (FPC 0) Prsnt BM0208327653 ex4200-24t 255 Master* Y 1 vcp-0
                                                      2 vcp-255/1/0
1 (FPC 1) Prsnt BM0208444177 ex4200-24t 254 Backup Y 3 vcp-255/1/0
                                                     0 vcp-1
2 (FPC 2) Prsnt BM0208372217 ex4200-24t 130 Linecard Y 4 vcp-0
                                                       0 vcp-255/1/0
                                                       3 vcp-255/1/1
3 (FPC 3) Prsnt BM0209074268 ex4200-24t 128 Linecard Y 1 vcp-255/1/0
                                                       2 vcp-255/1/1
4 (FPC 4) Prsnt LX0213337251 ex4550-32f 128 Linecard Y 2 vcp-255/2/0

Note that FPC4 is also connected to FPC1 using a 10 Gbit fiber optic VC connection. It is not listed here because I unplugged it. It was plugged when the problem occurred and when I restarted FPC0 and FPC1 the first times.

All the machines run Junos 12.3R3.4.

Many thanks in advance!

Adamo

Edit:

some more information:

- using packet sniffing on a linux host connected to one of the not forwarding ports I can see only LLDP packets coming from the switch

- spanning-tree is in forwarding state for all the ports that are not forwarding traffic

- traffic is not forwarded even on the same switch (tested by connecting two hosts on two different ports on the same VLAN of FPC1)

- when halting FPC1 using the display button, it shows "HALTING..." and never halts (at least after 15 minutes it was still not halted)