RE: Good question involving EIGRP & ISDN

[McCallum, Robert]

Everything works except once I shutdown one of the T1 interfaces and the BRI
comes up all the traffic continues to use the BRI even after I bring the T1 back online. 

 

Does this mean that you are using the BRI as a backup interface?  My understanding of floating static routes is that the BRI interface will be up but will not be used as the admin distance is greater.  When the initial link goes down then that route will be preferred.  If you are using backup interface then all you need on your t1 line is :-

 

backup interface bri0

backup delay 40 20.

 

40 = enable backup 40 seconds after the primary line failure.

20 = terminate the secondary 20 seconds after the primary line is reactivated.

 

hope this helps.

-----Original Message-----
From: Andre Fecteau [mailto:[EMAIL PROTECTED]]
Sent: 28 August 2000 10:38
To: [EMAIL PROTECTED]
Subject: Good question involving EIGRP & ISDN

Hello,

I have two locations connected by a T1 and ISDN(BRI).  The T1 is the main and the BRI is
meant as backup for just in case the T1 fails for some reason.  I have EIGRP running
between the T1 with a private addressing scheme.  I have a default route leading out through
the BRI interface with a Administrative Distance of 250.  The BRI interfaces as well as the
interface leading to the Internet are all passive interfaces so the routing info won't leak into
the internet.  I have a default route on the side of the T1 that has an interface leading to the
Internet.  Everything works except once I shutdown one of the T1 interfaces and the BRI
comes up all the traffic continues to use the BRI even after I bring the T1 back online.  I
want the BRI to go down and all traffic to resume using the T1 interface for obvious
reasons.  Can anyone tell me what's wrong with my configuration?  It works, but not
completely as needed!!!  Help!!!

Internet connected router:
router eigrp 10
 passive-interface Ethernet0/0
 passive-interface BRI1/0
 network X.X.X.X
 no eigrp log-neighbor-changes
!
ip nat inside source static X.X.X.X  X.X.X.X extendable
ip nat inside source static X.X.X.X  X.X.X.X extendable
ip nat inside source static X.X.X.X  X.X.X.X extendable
ip nat inside source static X.X.X.X  X.X.X.X extendable
ip nat inside source static X.X.X.X  X.X.X.X extendable
ip nat inside source static X.X.X.X  X.X.X.X extendable
ip classless
ip route 0.0.0.0 0.0.0.0 X.X.X.X   --- To the default gateway internet router.
ip route X.X.X.X  X.X.X.X  X.X.X.X  250 --- To the other side private.
 

Inside router (other side of T1):
router eigrp 10
 passive-interface BRI1/0
 network X.X.X.X
 no auto-summary
 no eigrp log-neighbor-changes
!
ip classless
ip route 0.0.0.0 0.0.0.0 X.X.X.X    --- To the T1
ip route X.X.X.X  X.X.X.X  X.X.X.X  250  --- To the BRI
no ip http server

Can I fix this problem by redistributing the static routes to eigrp?  And how do I do it?  Cause my attempts have failed, if that's a viable option anyway!

Thanks,
Andre