ISDN PRI D-Channel (23 or 24)

[Bruce Griffis]

I am having trouble bringing up the D channels on my 4700. I
have 2 ISDN PRI's from MCI. MCI does not see the D channel up. The
T1 is up (continuity), the D channel is not.

Specifics:

controller T1 0
framing esf
linecode b8zs
pri-group timeslots 1-24
!
controller T1 1
framing esf
linecode b8zs
pri-group timeslots 1-24
!
interface serial 0:23
(.....)

This looks to me like channel 23 is configured as the D
channel. MCI shows the D channel is supposed to be on channel 23 of
their T1. I tried changing to "interface serial 0:24" - but that
didn't work.

How do I specify channel 24 as the D channel?

[Dennis Clare]

>
>
> I am having trouble bringing up the D channels on my 4700. I
> have 2 ISDN PRI's from MCI. MCI does not see the D channel up. The
> T1 is up (continuity), the D channel is not.
>

Do you have a switchtype defined?

> Specifics:
>
> controller T1 0
> framing esf
> linecode b8zs
> pri-group timeslots 1-24
> !
> controller T1 1
> framing esf
> linecode b8zs
> pri-group timeslots 1-24
> !
> interface serial 0:23
> (.....)
>
> This looks to me like channel 23 is configured as the D
> channel. MCI shows the D channel is supposed to be on channel 23 of
> their T1. I tried changing to "interface serial 0:24" - but that
> didn't work.

The B-channels run B1-B23, and the D-channel is 24. But the serial interfaces
on cisco products start at zero. So is is Serial 0 - Serial 22 and the
D-channel is Serial 23. This is T1 of course.

Turn on the debug isdn q921 and debug isdn q931 for further information
and traces. Don't forget to configure the service timestamp.

Dennis

[Bill May]

Bruce Griffis wrote:
>
> I am having trouble bringing up the D channels on my 4700. I
> have 2 ISDN PRI's from MCI. MCI does not see the D channel up. The
> T1 is up (continuity), the D channel is not.
>

> Specifics:
>
> controller T1 0
> framing esf
> linecode b8zs
> pri-group timeslots 1-24
> !
> controller T1 1
> framing esf
> linecode b8zs
> pri-group timeslots 1-24
> !
> interface serial 0:23
> (.....)
>
> This looks to me like channel 23 is configured as the D
> channel. MCI shows the D channel is supposed to be on channel 23 of
> their T1. I tried changing to "interface serial 0:24" - but that
> didn't work.
>

> How do I specify channel 24 as the D channel?

Bruce,

You are confusing channel-group numbers (which is how cisco
internally numbers interfaces), with timeslots.

Timeslot 24 is typically used for T1 PRI lines. I do not
believe that you can specify to have a D channel in timeslot 23.

wbm