ISDN back-up for multiple Frame-Relay sub-interfaces

[m.tapping]

I'm intending to set-up BRI back-up from our customer sites using 'floating static routes'.

Is an individual subnet required for each BRI peer or can a single subnet from the main host be used across multiple BRI peers? Example:

Host Router host123:

interface Loopback0

ip address 172.18.48.1 255.255.255.0

!

interface Dialer1

ip unnumbered Loopback0

encapsulation ppp

dialer pool 1

dialer remote-name peer999

dialer string 1234567890

dialer-group 1

no fair-queue

pulse-time 0

ppp authentication chap

Peer Router peer999:

interface BRI0

ip address 172.18.48.2 255.255.255.0

encapsulation ppp

dialer map ip 172.18.48.1 name host123 broadcast 1234567890

dialer-group 1

no fair-queue

pulse-time 0

ppp authentication chap

repeated for other peers using addresses from range 172.18.48.0/24

[tepatel]

Same subnet will work as bri's are point to point interface in your case. So you can have multiple branch offices with bri ip address in the same subnet of HQ bri interface.

You can see following url for that

http://www.cisco.com/warp/public/793/access_dial/hdlc_12497.html

which has one branch with 10.9.9.2 255.255.255.0 while you can have other brcnahes with 10.9.9.3 to .254 etc.

[vcjones]

Why not just make both ends IP unnumbered? Gets rid of a lot of issues and allows you to use "obvious" IP's to identify each remote. KISS!

Good luck and have fun!

Vincent C Jones

www.networkingunlimited.com