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ISDN not Firing

navneet_78
Level 1
Level 1

I have an Bri0/0 interface configured as backup for serial 0/0 interface. When i manually make the leased line down , the ISDN is not firing.

But when i do a test call, i see ISDN is firing.

Also i see that the BRI0/0 interface status says shutdown. I tried clearing the BRI interface, still it remains the same.

Can you please tell me what the problem might be?

14 Replies 14

mheusinger
Level 10
Level 10

Hello,

if the BRI shows shutdown, then you have administratively set it to shutdown. Please configure

interface Bri0/0

no shutdown

On the other hand I would assume a test call would not work in this case anyhow, so I am unclear as to what the status really is. can you post your relevant router config?

Hope this helps! Please rate all posts.

Regards, Martin

Thanx for replying.

No the Bri0/0 interface is not in shut mode.

Here is the config for BRI0/0 and serial 0/0.

xxxxxxxxxxxxxxx#sh run int BRI0/0

Building configuration...

Current configuration : 652 bytes

!

interface BRI0/0

description *** to Reliance for MPLS backup ***

bandwidth 128

ip address 10.124.7.11 255.255.255.0

ip access-group Reliance_MPLS in

ip access-group Reliance_MPLS out

encapsulation ppp

dialer map ip 10.124.7.4 name Ludhiana1@xxx.com broadcast 3033525

dialer load-threshold 5 either

dialer-group 1

isdn switch-type basic-net3

isdn point-to-point-setup

no fair-queue

ppp authentication pap callin

ppp chap hostname Ludhiana1@xxx.com

ppp chap password xxx

ppp pap sent-username Ludhiana1@xxx.com password xxx

ppp multilink

crypto map ludhiana_isdn

end

xxxxxxxxxxxxxxxxxxxxx1#

cap_cw_hin_vpn_ludhiana1#sh run int Serial0/0

Building configuration...

Current configuration : 317 bytes

!

interface Serial0/0

description *** 2M MPLS ; Reliance LUDHI_NSP_CIR_98191 ; a70-024 ***

ip address 10.124.4.37 255.255.255.252

ip access-group Reliance_MPLS in

ip access-group Reliance_MPLS out

encapsulation ppp

backup interface BRI0/0

no fair-queue

no dce-terminal-timing-enable

crypto map mpls_map

end

cap_cw_hin_vpn_ludhiana1#

Hope that helps.

Also it is in shutdown mode, when i issue the SH isdn status command. It should show deactivated.

xxxxxxxxxxxxxx#sh isdn sta

Global ISDN Switchtype = basic-net3

ISDN BRI0/0 interface

dsl 0, interface ISDN Switchtype = basic-net3

Layer 1 Status:

SHUTDOWN

Layer 2 Status:

Layer 2 NOT Activated

Layer 3 Status:

0 Active Layer 3 Call(s)

Active dsl 0 CCBs = 0

The Free Channel Mask: 0x00000000

Total Allocated ISDN CCBs = 0

xxxxxxxxxxxxxxx#

Hello,

first of all: could you please IMMEDIATELY change your password on the dialer! This is easily decodeable and you should never post your username/password settings.

Second: looks like ISDN layer 1 does not work. Are you sure cabling and ISDN switch type are correct?

Regards, Martin

Can you remove the backup interface from the serial 0/0. That is why the BRI is in shutmode. Your BRI line wudnt come up until the serial is down.

Or shall the Bri0/0 status be in Up Up(spoofing).

Since Layer 1 is not even up, i think verification of the connection will solve your problem.....

If u happen to have a bri0/1, try swapping itto see how it goes.

There is only one BRI port on the router.

I have changed the cable and also resetted the NT1 box, still the ISDN is not firing.

NT1 box led staus is :: status led: off , power: on

ISDN is firing when iam able to do a test call, then it means the line is fine..right??

How do i troubleshoot further on this?

Hi

As Gautam pointed out the backup interface command under the serial interface will put your isdn bri interface in shutdown mode once you issue shutdown command under the main serial interf

you can better switch off the leased line modem and check for the logs.also try to get the isdn debug outputs both q921 as well as q931..

that will def help to troubleshoot your problem..

regds

Hi Navneet,

Can you pls post the output of "debug dialer" as soon as primary link is made down?

Are you also enabling ip traffic using "dailer-list"?

HI

Can u explain why u have placed access-group when u have already placed a dailer-group i think u can go for dailer-group as its eqvivalent to access-list in terms of ISDN and i think in ISDN we have to go for dailer-group instead of access-group.so in ur case u r using access-group as well as dailer- group i think this is due this.can u check by removing u r access-group statements.

Thanks

Mahmood

Mahmood is wrong. Access-group and dialer-group are entirely diffrerent commands.

dialer-group is for triggering the ISDN connection(interested traffic).

access-group is filtering the traffic passing through that interface with the corresponding accesslist.

You try to troubleshoot this way

First switch-off the LL modem and try to ping the outer IP.

type sh isdn status command

and check the Layer 1 and 2 satus.

If layer 1 is active and Layer 2 is ready to accept multiple frames

create a user which is there in the other router and give same password given there.

If this is also no solving

try to do the same with another BRI port of same or different router.

Hi ratheeshrg

Thanks for clarifying me.

Thanks

Mahmood

Hi,

u should have some traffic flowing for the link to come up even if it is backup interface. try keeping an continous ping from remote end and then bring down the serial interface. configuration looks fine and bri should come up. remove the isdn point to point setup as it is useless. comes by default all the time.

imranmohd
Level 1
Level 1

Hi Navneet

Try configuring backup delay.Also could u send the configuration

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