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Community Member

1603 isdn dial problem

--begin ciscomoderator note-- The following post has been edited to remove potentially confidential information. Please refrain from posting confidential information on the site to reduce security risks to your network. -- end ciscomoderator note --

Can anyone help, I am having problems with the isdn on a 1603 router. The config below is one i took straight out of a cisco manual so i assume it is ok, but i stll cant get the bri port to dial. I have checked the isdn line with other equipment and they are fine. i am trying to dial an adtran over isdn. All i want to see at this stage is that the cisco has dialled.

please find attached a copy of the config i have on the 1603, and an output when i try to ping ( with debug q921,931, and dialer switched on):

router config :

Router#sh run

Building configuration...

Current configuration:


version 11.3

service timestamps debug uptime

service timestamps log uptime

no service password-encryption


hostname Router



username cisco-b xxxxxxxx0 xxxxxxxx

isdn switch-type basic-net3




interface Ethernet0

no ip address



interface BRI0

ip address

encapsulation ppp

dialer idle-timeout 300

dialer map ip name cisco-b xxxxxxxxxxxxxxxx

dialer-group 1

ppp authentication chap


ip classless

ip route


dialer-list 1 protocol ip permit


line con 0

line vty 0 4




and here is the output from a ping :


Type escape sequence to abort.

Sending 5, 100-byte ICMP Echos to, timeout is 2 seconds:

00:35:59: BRI0: Dialing cause ip (s=, d=

00:35:59: BRI0: Attempting to dial --moderator edit-- xxxxxxxxxxxx

00:35:59: ISDN BR0: TX -> IDREQ ri = 48769 ai = 127 .

00:36:01: ISDN BR0: TX -> IDREQ ri = 42642 ai = 127 .

00:36:03: ISDN BR0: TX -> IDREQ ri = 4019 ai = 127 .

00:36:05: %ISDN-6-LAYER2DOWN: Layer 2 for Interface BR0, TEI 255 changed to down


00:36:07: BRI0: wait for carrier timeout, call id=0x800A.

Success rate is 0 percent (0/5)

Any suggestions would be great. By the way the sh isdn stat shows deactivated and the bri light(s) on the cisco are not /have not lit. As i say thought the lines are good.



Re: 1603 isdn dial problem

Router is definitely trying to dialout but layer 2 is not coming up. Router is sending

q921 IDREQuest to get a TEI assigned by the switch, but we don't see IDASSN

(ID assign) back from the switch in response to that.



Re: 1603 isdn dial problem

Can you please try adding "isdn tei-negotiation first-call " under the BRI 0.

Also ensure the SPIDS are correctly specified if required by the telco:

Please refer to:

Thanks, Mak.

Community Member

Re: 1603 isdn dial problem

"sh isdn stat" should indicate "ACTIVE" in Layer 1 and "MULTIPLE_FRAME_ESTABLISHED" in Layer 2. If either if these antries aren't there, don't bother attempting to dial, as it will definitely fail.

Also, try to clear up the BRI interface by issuing the "clear int bri0". You can also do a "shut" and "no shut" on the BRI interface to try to reset the link. Sometimes, rebooting also helps.

If that didn't work, check with your provider if you're using the correct ISDN switch-type. Also, if you're in a region that requires you to put in some SPIDs (also provided by your provider), you will need to do so using the following commands under the BRI interface config:

isdn spid1

isdn spid2

In the end, your "sh isdn stat" should look something like the following example output: (Taken from a 2600 router)

sh isdn stat

Global ISDN Switchtype = basic-ni

ISDN BRI0/0 interface

dsl 0, interface ISDN Switchtype = basic-ni

Layer 1 Status:


Layer 2 Status:



TEI 111, ces = 1, state = 5(init)

spid1 configured, spid1 sent, spid1 valid

Endpoint ID Info: epsf = 0, usid = 1, tid = 1

TEI 112, ces = 2, state = 5(init)

spid2 configured, spid2 sent, spid2 valid

Endpoint ID Info: epsf = 0, usid = 3, tid = 1

Layer 3 Status:

0 Active Layer 3 Call(s)

Active dsl 0 CCBs = 0

The Free Channel Mask: 0x80000003

Total Allocated ISDN CCBs = 0

Community Member

Re: 1603 isdn dial problem

Try the next config, might work:

Global config:


isdn switch-type basic-net3


interface BRI0

no ip address

encapsulation ppp

dialer pool-member 1 max-link 1

isdn switch-type basic-net3

ppp authentication chap pap callin


interface Dialer1

description TEST

ip address negotiated

no ip proxy-arp

encapsulation ppp

no ip split-horizon

dialer pool 1

dialer idle-timeout 300

dialer string class DialClass

dialer hold-queue 10

dialer load-threshold 10 either

dialer-group 1

ppp authentication chap pap callin

ppp chap hostname

ppp chap password

ppp pap sent-username password


map-class dialer DialClass

dialer-list 1 protocol ip permit

Good luck.


IDJ van der Ven

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