Hi There,
One of our client has a Nortel Meridian PBX and they are cutting over to Cisco 2800 gateway as the PBX is unstable and could break anytime. We have a Call manager cluster in the Datacentre with a local gateways.
Background:
First we thought it was an ISDN PRI circuit and when we plugged in the E1 cable the alarm LED was on and L1.L2 and L3 were down. After working on the circuit and debugging the router we found the circuit is not ISDN it's an older circuit called DTI (Digital Trunk Interface) or CAS (Channel Associated signalling) which I never came across before but is supported on G.703 VWIC-1MFT card from Cisco. I got a Cisco 2800 router which had G.703 card and plugged the E1 cable and the L1 was up but L2 and L3 were having issue's.
I don’t understand the G.703 protocol as I couldn’t find much document online and how can I configure the router. Please see attachment diagram on how it is configured.
Errors:
router#sh isdn status
Global ISDN Switchtype = primary-net5
ISDN Serial0/0/0:15 interface
dsl 0, interface ISDN Switchtype = primary-net5
Layer 1 Status:
ACTIVE
Layer 2 Status:
TEI = 0, Ces = 1, SAPI = 0, State = TEI_ASSIGNED
Layer 3 Status:
0 Active Layer 3 Call(s)
Active dsl 0 CCBs = 0
The Free Channel Mask: 0xFFFF7FFF
Number of L2 Discards = 0, L2 Session ID = 39
Total Allocated ISDN CCBs = 0
router#
Dec 8 05:11:09.310: ISDN Se0/0/0:15 Q921: L2_Es
router#sh controller e1
E1 0/0/0 is up.
Applique type is Channelized E1 - balanced
No alarms detected.
alarm-trigger is not set
Version info Firmware: 20090113, FPGA: 20, spm_count = 0
Framing is NO-CRC4, Line Code is HDB3, Clock Source is Line.
Data in current interval (86 seconds elapsed):
0 Line Code Violations, 0 Path Code Violations
0 Slip Secs, 0 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins
0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs, 0 Unavail Secs
Total Data (last 1 15 minute intervals):
0 Line Code Violations, 0 Path Code Violations,
0 Slip Secs, 0 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins,
0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs, 0 Unavail Secs
router#
Dec 8 05:16:15.311: ISDN Se0/0/0:15 Q921: L2_EstablishDataLink: sending SABME
Dec 8 05:16:15.311: ISDN Se0/0/0:15 Q921: User TX -> SABMEp sapi=0 tei=0
Dec 8 05:16:16.311: ISDN Se0/0/0:15 Q921: User TX -> SABMEp sapi=0 tei=0
Dec 8 05:16:17.311: ISDN Se0/0/0:15 Q921: User TX -> SABMEp sapi=0 tei=0
Dec 8 05:16:18.311: ISDN Se0/0/0:15 Q921: User TX -> SABMEp sapi=0 tei=0
Dec 8 05:16:24.311: ISDN Se0/0/0:15 Q921: L2_EstablishDataLink: sending SABME
Dec 8 05:16:24.311: ISDN Se0/0/0:15 Q921: User TX -> SABMEp sapi=0 tei=0
Dec 8 05:16:25.311: ISDN Se0/0/0:15 Q921: User TX -> SABMEp sapi=0 tei=0
Dec 8 05:16:26.311: ISDN Se0/0/0:15 Q921: User TX -> SABMEp sapi=0 tei=0
Dec 8 05:16:27.311: ISDN Se0/0/0:15 Q921: User TX -> SABMEp sapi=0 tei=0
Dec 8 05:16:33.311: ISDN Se0/0/0:15 Q921: L2_EstablishDataLink: sending SABME
Dec 8 05:16:33.311: ISDN Se0/0/0:15 Q921: User TX -> SABMEp sapi=0 tei=0
Dec 8 05:16:34.311: ISDN Se0/0/0:15 Q921: User TX -> SABMEp sapi=0 tei=0
Dec 8 05:16:35.311: ISDN Se0/0/0:15 Q921: User TX -> SABMEp sapi=0 tei=0
Dec 8 05:16:36.311: ISDN Se0/0/0:15 Q921: User TX -> SABMEp sapi=0 tei=0
Dec 8 05:16:42.311: ISDN Se0/0/0:15 Q921: L2_EstablishDataLink: sending SABME
Dec 8 05:16:42.311: ISDN Se0/0/0:15 Q921: User TX -> SABMEp sapi=0 tei=0
Dec 8 05:16:43.311: ISDN Se0/0/0:15 Q921: User TX -> SABMEp sapi=0 tei=0
Dec 8 05:16:44.311: ISDN Se0/0/0:15 Q921: User TX -> SABMEp sapi=0 tei=0
Dec 8 05:16:45.311: ISDN Se0/0/0:15 Q921: User TX -> SABMEp sapi=0 tei=0
Dec 8 05:16:51.311: ISDN Se0/0/0:15 Q921: L2_EstablishDataLink: sending SABME
Dec 8 05:16:51.311: ISDN Se0/0/0:15 Q921: User TX -> SABMEp sapi=0 tei=0
Dec 8 05:16:52.311: ISDN Se0/0/0:15 Q921: User TX -> SABMEp sapi=0 tei=0
Dec 8 05:16:53.311: ISDN Se0/0/0:15 Q921: User TX -> SABMEp sapi=0 tei=0
Dec 8 05:16:54.311: ISDN Se0/0/0:15 Q921: User TX -> SABMEp sapi=0 tei=0
Dec 8 05:17:00.311: ISDN Se0/0/0:15 Q921: L2_EstablishDataLink: sending SABME
Thank you for all your help in advance.
