Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Announcements

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

New Member

pri b-channel problem

We have a ISDN pri line in Seul connected to a router 2620 (MPC860) on which runs the ios c2600-js-mz.122-7b.bin.

Here is a part of the router configuration :

username xxxxxx password 7 xxxxxxxxxxx

username xxxxxx password 7 xxxxxxxxxxx

controller E1 1/0

framing NO-CRC4

linecode ami

pri-group timeslots 1-31

!

interface Serial1/0:15

description PRI Numero xxxxxxxxxxxx

bandwidth 2048

no ip address

encapsulation ppp

load-interval 30

dialer pool-member 1

isdn switch-type primary-net5

no fair-queue

ppp link reorders

ppp multilink

ppp timeout idle 300 either

!

interface Dialer0

ip address xxxxxxxx xxxxxxxx

no ip unreachables

encapsulation ppp

dialer pool 1

dialer idle-timeout 300 either

dialer string xxxxxxxxxxxxx

dialer-group 1

no cdp enable

ppp authentication chap

ppp chap hostname xxxxxxxx

ppp multilink

multilink min-links 30

!

Here are results of the command debug ISDN q921:

Nov. 26 10:46:59 UTC: ISDN Se1/0:15: TX - > SABMEp c/r=0 sapi=0 tei=0

Nov. 26 10:47:00 UTC: ISDN Se1/0:15: TX - > SABMEp c/r=0 sapi=0 tei=0

Nov. 26 10:47:01 UTC: ISDN Se1/0:15: TX - > SABMEp c/r=0 sapi=0 tei=0

Nov. 26 10:47:02 UTC: ISDN Se1/0:15: Vent: received NL_REL_IND

and those of the command debug ISDN event:

Nov. 26 10:48:05 UTC: ISDN Serial1/0:15: isdn_is_bchannel_available: No Free B-channels.

Nov. 26 10:48:07 UTC: ISDN Serial1/0:15: isdn_is_bchannel_available: No Free B-channels.

Nov. 26 10:48:09 UTC: ISDN Serial1/0:15: isdn_is_bchannel_available: No Free B-channels.

Nov. 26 10:48:11 UTC: ISDN Serial1/0:15: isdn_is_bchannel_available: No Free B-channels.

Nov. 26 10:48:13 UTC: ISDN Serial1/0:15: isdn_is_bchannel_available: No Free B-channels.

sh isdn status

Global ISDN Switchtype = primary-net5

ISDN Serial1/0:15 interface

dsl 0, interface ISDN Switchtype = primary-net5

Layer 1 Status:

ACTIVE

Layer 2 Status:

TEI = 0, Ces = 1, SAPI = 0, State = TEI_ASSIGNED

I_Queue_Len 0, UI_Queue_Len 0

Layer 3 Status:

0 Active Layer 3 Call(s)

Active dsl 0 CCBs = 0

The Free Channel Mask: 0x7FFF7FFF

Number of L2 Discards = 0, L2 Session ID = 10

Total Allocated ISDN CCBs = 0

I would like to know what could be the cause of the unavailability of the b-channel and also why the state of layer 2 is not in MULTIPLE_FRAME_ESTABLISHED

Thanks

1 REPLY
Cisco Employee

Re: pri b-channel problem

Since the SABMEp's from the router is not replied by telco to sync-up layer 2, it looks like a probelm in the telco switch..So you need to talk to telco company to get it fixed..However you can try to follow the docs below to see the E1-controller hardware is good or not by doing a hardware loopbak test

http://www.cisco.com/warp/public/116/e1_hard_loopback.html

Now here is the good doc for troubleshooting for E1 lines

http://www.cisco.com/warp/public/116/E1_pri.html

130
Views
0
Helpful
1
Replies
CreatePlease login to create content