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New Member

ISDN dial to MPLS and HQ Problems...need help.


I've a situation where I've two ISDN call backup using 1 BRI for my branch connection. First, the call will go to a nearest MPLS node, if this is failed, its will call to a second dialer string to my HQ. (there is 2 router at HQ, one connected to MPLS (3800), and second for ISDN and VOIP call(3640)).

The problem occur when everytime the ISDN call to MPLS, everything are OK. Then, when I disconnect the isdn dial to MPLS ( so it will call to HQ ), I can't access HQ.

If at first I call HQ and then MPLS, everything ok. But if I call back HQ after MPLS call, it can't route. From HQ 3800 router, I can see the route keep on searching at MPLS cloud and back to HQ router (looping).

At branch, the routing are to BRI1/0 :-

ip route BRI1/0

ip route BRI1/0

interface BRI1/0

ip unnumbered Loopback1

encapsulation ppp

dialer string 123456

dialer string 789011

dialer load-threshold 1 either

dialer-group 1

isdn switch-type basic-net3

isdn point-to-point-setup

ppp authentication chap callin

ppp chap hostname xxxxx

ppp chap password xxxxx

ppp multilink

ppp multilink load-threshold 1 either


**Both string configure at int BRI1/0, no int dialer used.

At HQ ISDN router i put this route :-

ip route 192.168.x.x 200

At HQ 3800 router i put :-

ip route 182.x.x.x 220

(182.x.x.x = MPLS node ip)

Need helps. Thanks.

  • MPLS
New Member

Re: ISDN dial to MPLS and HQ Problems...need help.

please check the foll

1. whether the bri interface ip in the branch1 router (loopback 1) has a proper reverse route in the MPLS cloud.

2. from the mpls pe connecting to the hq, pls chk the routing info for the destination to be reached.

New Member

Re: ISDN dial to MPLS and HQ Problems...need help.

hi jarvar,

I've already solve this problems. Its due to tracking time out problem. Thanks.