BOD solution by serial and ISDN connections with 3 routers

[k9842]

Hi maybe I' m in the wrong forum, but perhaps somebody could help me out there.

I'm looking for an BOD solution for an SOHO office with an 64 Kbit/s leased line.

Imagine the following Situation

Site A has 2 routers, router 1 and 2 which are interconnected via crosslink and are working as an HSRP pair.

Router 3 is at the remote site C

Router 3 has an 64kbit/sec leased line to router 1

Router 3 has an 2*64 KBit/sec ISDN Backup Dialer to router 2

routing protocol is ospf

In peak moments additional Bandwidth is needed.

I thought about a solution via Multichassis Multilink by combining the ISDN channels and the serial link but can't say if this works.(Multilink or dialer interface definition?)

Requirements are that the leased line is the only link up and running during low peak times. An ISDN backup must be available when the leased line is down

There mustn' t be any problemes due to chap usernames and passwords for an possible differentiating of the multilink interface.

Any experience with situations like that.

Regards

Andreas

[umedryk]

Not sure if Chap is needed in this scnario. I believe pap is enough.

[rakshitj]

Hi,

If you wanted to use ISDN as backup link (i.e. when your Lease Line fails and ISDN should get active).

You can add following command on serial interface

int s0

backup delay 5 10

backup interface b0/0 (interface of your BRI Port)

and add floating routes if possible with higher Metric then OSPF.

Use propr IP scheme on your BRI Interface at both the end.

This solution should work 100%.