Question : Nortel PBX server is down

I have Nortel PBX CS1000S. The full set is (Signaling Server, Call Server, and Gateway Media).
this morning I found all telephone sets are down and gave a message says (Server unreachable). so I did restart the whole set but still gives the same error.
The MC-32 Card on the Gateway media says on the LED S009 "but I checked ELAN and it is operational" even when I connect my computer to the serial port on the signaling server and try to login using "CSLogin" it says :
Connect: S_errorNo EHOSTDOWN.

Please advice as my whole system is down.

Thanks
Mostafa

Answer : Nortel PBX server is down

Make sure your LAN connection is working. Check the network cable, router port to the PBX is active and that the PBX is not configure for DHCP.  If it is configure for DHCP it could be it recieve a differrent IP address and all handset and other devices are unable to communicate with it.

Good luck.