cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
840
Views
0
Helpful
11
Replies

ISDN PRI

JeffG1
Level 3
Level 3

I cannot get my Isdn pri to come up with its layer 2.

isdn status shows:

Layer 2 Status:

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

Serial1/0:23 shows

Serial1/0:23 is up, line protocol is down

The T1 says everything is fine

here is my config for each

controller T1 1/0

framing esf

linecode b8zs

pri-group timeslots 1-24

description PRI to Qwest

!

interface Serial1/0:23

no ip address

encapsulation ppp

no logging event link-status

isdn switch-type primary-ni

isdn incoming-voice voice

!

voice-port 1/0:23

!

Am I missing something? Qwest says the T1 is fine and they are sending me all my channels, but they do not see anything on the D channel.

11 Replies 11

yraps
Level 1
Level 1

What about the clocking?

You can add the clock support under the line with follwing command:

clock source line primary

If that deosn't help are you sure you framing and coding for the line are ok? Please verifiy that with your line provider else you can use T-berd equipment.

Robert Salazar
Cisco Employee
Cisco Employee

What do you see from a debug isdn q931?

I think he means q921. Turn on debug isdn q921. Have you determined who is network or user? Ask the telco if they are set for user or network. If you cant get that info, go under the serial interface and enter "isdn network". Right now you are set for user. This command will make you network. Then look at the q921 debug. You should see packets being TX and RX. Also try a loopbakc plug. The layer 2 wont come up with a loopback plug. But it will allow you to determine if you can RX and TX packets.

JeffG1
Level 3
Level 3

The clock source is Line,

On a debug q921 I see the following

ISDN Se1/0:23: TX -> SABMEp c/r = 1 sapi = 0 tei = 0

00:05:54: %CONTROLLER-5-UPDOWN: Controller T1 1/0, changed state to down (RAI detected)

00:05:55: ISDN Se1/0:23: Event: received MNL_RESET_REQ

setting isdn network didnt change anything.

Have you troubleshot the line? The RAI means Remote Alarm Indicator. This is sent back on the line when there is a failure down stream. For example if you have four nodes inbetween you and the end point and there is a failure inbetween nodes B and C, node C receives an LOS from B (actually generated at C by the loss of signal). Node C generates an AIS (Alarm Indication Signal) to node D to indicate that the line problem is before node C. Node C attempts to send back an RDI (Remote Defect Indicator) or an RAI to node B if the opposite side of the line is up to alert the upstream nodes (A and B) or the failure. Since you are seeing an RAI I would expect you have a remote failure of some sort. If there is no other service on this line, i.e it is not on a multiplexed bearer circuit, ask the carrier to execute a series of loopback tests to rule out this possibility.

Pabloduarte
Level 1
Level 1

Hello Jeff,

I have just finished an extensive month with qwest installing 4 ISDN PRI's.

I can tell you From experience that they are not the most knowledgeable company to work with.

I was lucky to have other equipment besides my router to Troubleshoot the T1's. Even then the troubleshooting process to on a new meaning with Qwest.

My suggestion is to have the Qwest Technician hook up his T-berd and not only check for T1 ,Framing and Linecode, but actually emulate the ISDN Switch. Only the will you have the confidence to start looking at your equipment.

Also make sure that the ISDN switch type is the correct one.

ON another note, Can you provide the Router type you are connecting to as well as the Version of IOS.

Good Luck

Pablo

Use-

debug isdn q921

Then you will see if you are TX and RX sabme. If you arent RX determine also who is network or user. IF you find everything is set right use a loopback plug and see if you RX what you TX. That will verify HW and SW are correct. This is all assuming the switch type is correct. I would guess your linecoding and framing are correct or else the T1 wouldnt come up.

JeffG1
Level 3
Level 3

Uggg it ended up being a loop downstream.

Now I just need to fix incoming calls, we have DID and when you dial a number you get a dial tone...

Fear not, this one's easy.

In your dial-peers that go to the PRI "POTS" add direct-inward-dial.

dial-peer voice 9 pots

destination pattern 9.......

forward digits 7

port 1/0:23

diarect-inward-dial

-Brian

Pabloduarte
Level 1
Level 1

Jeff try adding the following Dial Peer

dial-peer voice 999 pots

incoming called-number ..

direct-inward-dial

port 1/0:23

It should do the Job.

Good Luck

I had to add a translation rule to translate my three digits that Qwest was giving me into 4 digits. After that everything worked ok.