Hello!
I'm trying to configure a ISDN backup link on a Cisco. Each time I reset the BRI it takes about 15 seconds until the session will be terminated from the Swisscom's side. Call out is only possible (but working) during this 15 second time frame.
Layer 1 is activated permanently since several years and working OK.
Following [1], I debugged the link:
[1] http://www.cisco.com/warp/public/129/bri-layer2.html
---8<--- Mar 1 01:26:39: ISDN BR0 Q921: User TX -> IDREQ ri=44602 ai=127 Mar 1 01:26:39: ISDN BR0 Q921: User RX <- IDASSN ri=44602 ai=89 Mar 1 01:26:39: ISDN BR0 Q921: L2_EstablishDataLink: sending SABME Mar 1 01:26:39: ISDN BR0 Q921: User TX -> SABMEp sapi=0 tei=89 Mar 1 01:26:39: ISDN BR0 Q921: User RX <- UAf sapi=0 tei=89 Mar 1 01:26:39: %ISDN-6-LAYER2UP: Layer 2 for Interface BR0, TEI 89 changed to up Mar 1 01:26:49: ISDN BR0 Q921: User RX <- RRp sapi=0 tei=89 nr=0 Mar 1 01:26:49: ISDN BR0 Q921: User TX -> RRf sapi=0 tei=89 nr=0 Mar 1 01:26:54: ISDN BR0 Q921: User RX <- DISCp sapi=0 tei=89 Mar 1 01:26:54: %ISDN-6-LAYER2DOWN: Layer 2 for Interface BR0, TEI 89 changed to down Mar 1 01:26:54: ISDN BR0 Q921: User TX -> UAf sapi=0 tei=89 Mar 1 01:26:54: ISDN BR0 Q921: L2_EstablishDataLink: DISC received & not Passive-shutdown SABME will not be sent. ---8<---
Cisco says "If the DISC message originated from the ISDN switch, contact the telco." But on the Swisscom-side, nobody is able to understand my problem or willing to help.
Any hint what I should say to the "Swisskomiker" to get the right solution? Anyone here who knows a magic keyword in IOS to disable the need for a permanent Layer 2 connection?
Thanks! Beat