03-12-2009 11:05 AM
Dear Friends ,
I am facing a peculiar issue with ISDN .
For a particular customer , in a 3 tier architecture ,we use 2 backups .
backup 1 , if the leased line fails , the access router fires the isdn ,connecting it to the distribution layer .
If backup 1 fails , we manually fire isdn form the core router to the access site .
Now the issue is , I am not able to call my access site from the core . But strange enough , I am able to fire a test call to the core from the same access router.
I have racked my brain on this .
Need your help to arrive towards a solution.
Thanks
Warm Regards
Glenn.
03-12-2009 11:23 AM
Hi Glenn
do post out a N/W diagram along with the relevant config of the routers.
regds
03-12-2009 11:45 AM
Glenn
I have seen a scenario that produces results very much like the issue that you describe. The scenario involves configuring a router with dial where dialer profiles are configured. In the configuration there is authentication configured in the dialer profile but not configured on the physical interface (BRI or whatever). Since outgoing calls use the dialer profile where authentication is configured the call can authenticate and the call is successful. But an incoming call rings the physical interface, but since it does not have authentication configured it can not authenticate and the incoming call fails.
So is it possible that the remote access router is configured with dialer profiles, and that the dialer profile has authentication but the physical interface does not have authentication configured?
HTH
Rick
03-12-2009 10:30 PM
hey Rick ,
The configuration for the Remote BRI is
interface BRI0/0/0
no ip address
encapsulation ppp
dialer pool-member 1
isdn switch-type basic-net3
isdn point-to-point-setup
ppp authentication chap
ppp multilink
The authentication is configured on the physical interface.
But i feel some how , the call is not even landing on the remote end!
03-13-2009 01:12 AM
for the core
controller E1 1/0
pri-group timeslots 1-31
!
controller E1 1/1
pri-group timeslots 1-31
track timer interface 5
!
track 123 rtr 1 reachability
delay down 5 up 5
!
!
!
!
!
interface FastEthernet0/1
no ip address
shutdown
duplex auto
speed auto
!
interface Serial1/0:15
no ip address
encapsulation ppp
dialer rotary-group 1
dialer-group 1
isdn switch-type primary-net5
ppp authentication chap
ppp multilink
!
interface Serial1/1:15
no ip address
encapsulation ppp
dialer rotary-group 1
dialer-group 1
isdn switch-type primary-net5
ppp authentication chap
ppp multilink
!
interface Dialer1
bandwidth 2048
ip address 172.17.0.1 255.255.128.0
encapsulation ppp
no ip split-horizon
dialer in-band
dialer idle-timeout 300000
dialer load-threshold 1 either
dialer-group 1
ppp authentication chap
ppp multilink
!
interface Dialer2
ip address 172.29.1.2 255.255.255.0
encapsulation ppp
no ip split-horizon
dialer in-band
dialer idle-timeout 300000
dialer load-threshold 1 either
dialer-group 1
ppp authentication chap
ppp multilink
!
interface Dialer10
no ip address
!
interface Dialer12
no ip address
!
interface Dialer21
no ip address
!
access-list 101 permit ip any any
access-list 161 deny ip any host 172.25.4.53
dialer-list 1 protocol ip permit
!
end
------------------------
At the access.
!
interface BRI0/0/0
no ip address
encapsulation ppp
dialer pool-member 1
isdn switch-type basic-net3
isdn point-to-point-setup
ppp authentication chap
ppp multilink
!
!
!
interface Dialer1
description ### ISDN VADODRA NAP ###
bandwidth 64
ip address 172.23.125.244 255.255.255.128
encapsulation ppp
dialer pool 1
dialer remote-name VAD-RTR-02
dialer idle-timeout 300
dialer string
dialer load-threshold 125 either
dialer-group 1
ppp authentication chap
ppp multilink
!
interface Dialer2
description ### ISDN , DC ###
bandwidth 64
ip address 172.17.3.238 255.255.128.0
encapsulation ppp
dialer pool 1
dialer remote-name DC-ISDN-RTR-01
dialer idle-timeout 300
dialer load-threshold 125 either
dialer-group 1
ppp authentication chap
ppp multilink
!
!
ip classless
ip route 0.0.0.0 0.0.0.0 Dialer1 172.23.125.129 100 track 1
ip route 0.0.0.0 0.0.0.0 Dialer2 172.17.0.1 200 track 2
ip route 0.0.0.0 0.0.0.0 Serial0/1/0
ip route 0.0.0.0 0.0.0.0 Dialer3 172.17.128.1 250
!
access-list 101 permit ip any any
dialer-list 1 protocol ip list 101
!
Some part of the configuration are clipped for obvious reasons!
03-13-2009 09:02 AM
Glenn
I am not sure why the remote includes isdn point-to-point-setup in the configuration of the BRI. I have seen some situations where having that in the config did create some problems. I suggest that you remove it and see if the behavior changes.
If the problem still is going on then I would suggest that it might be helpful to do some more testing, trying to make a call from the core while running debug isdn q931 and perhaps debug ppp authentication.
HTH
Rick
03-16-2009 12:07 AM
Hi,
Please check with the isp if you have the PRI lines for both usage.
Incomming as well as outgoing. This may be the problme with the ISP.
What Rburts said before about incomming call makes sence since you configuration also is right it does not seems to be problem.
I also see SLA Configuration do u know what you are tracking ?
Hope this helps.
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