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New Member

Frame-Relay and ISdn Backup

Hello people,

Awesome forum. A wealth of information I hope I can grasp. My question is concerning Isdn Dial-Backup for Frame-Relay.

Question: The frame-relay subinterface never goes down thus the remote side kind of load balances but since the Frame is down there is packet loss. I specified a floating static route but that did not help because I think the Frame relay route never goes out of the routing table. Not using any routing protocols only static routes. Would I have to use a Routing Protocol to achieve this? In that case would RIP be acceptable? Thank you for your help.


Re: Frame-Relay and ISdn Backup

Absolutely. Use a routing protocol. RIP would be just fine.


Re: Frame-Relay and ISdn Backup


You can use Frame-Relay End-To-End Keepalives (FREEK) on the subinterface and DLCI you want to backup. FREEK makes backup more reliable.

With FREEK, You configure both the DLCIs on each end for FREEK and they send a keepalive between the routers. If one side has a issue (frame switch, circuit, router prob, etc) the other end won't get the keepalive and after 3 are missed (default) IOS forces the subinterface down where this DLCI is configured which kicks in the backup interface.

Sample cfg:

New Member

Re: Frame-Relay and ISdn Backup

We use the Dialer Watch feature of IOS to back up our frame relay with ISDN and even though it's a little tricky to set up and tweek to suit your needs, it's very reliable and "tweekable". It does require a routing protocol to key off of - we use OSPF.