Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Announcements

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

New Member

Leased line, 1 ISDN lines Backup configuration

Hi all,

I have a router with one leased line, one isdn line, where LL is the primary connection to HO, and isdn line is the backup.

now i have a DR site where in case both LL and ISDN fails to head office, it should diasl out to DR site.

How can i configure second option in the same ISDN on the same router.

Thank you all for in advance for the help.

4 REPLIES

Re: Leased line, 1 ISDN lines Backup configuration

ISDN-PRI or ISDN-BRI? Destination IP/Port the same?

Try this;

interface Dialer0

ip address w.x.y.1 255.255.255.248 << Note: HO should be w.x.y.2/29 and DR should be w.x.y.3/29

encapsulation ppp

dialer pool 1

dialer idle-timeout 600

dialer string HO_Dialer_String

dialer string DR_Dialer_String

dialer-group 1

ppp authentication chap

ppp multilink

!

dialer-list 1 protocol ip list 100

!

access-list 100 permit ip source_ip source_mask destination_ip destination_mask

When LL to HO fails, it will trigger ISDN to dial the first Dialer_String (HO ISDN Number), if it fails it will trigger the second Dialer_String (DR ISDN Number). You decide on the routing (use floating static route).

New Member

Re: Leased line, 1 ISDN lines Backup configuration

Hi Medan,

I use different IP range in DR site ISDN, even the is it possible.?

thanks,,

Re: Leased line, 1 ISDN lines Backup configuration

It is possible (it works for both) that configuration actually I use for ISDN-BRI with HO and DR IP range differs. The remote site of course will/should try to connect to DR site IP Address range when they could not connect to HO IP Address range. Take note that the ISDN Interface of 3 routers should use an IP Addresses in the same broadcast /29. You also have to put the destination IP Address range in the same ACL.

If its ISDN-PRI, the configuration differs a little bit.

New Member

Re: Leased line, 1 ISDN lines Backup configuration

hi pradeep,

please look into this config,i think this matches your scenario.

pls rate if it helps

Binoy

129
Views
10
Helpful
4
Replies