Fall Back

[abhishekbanik]

Hello ,

Is is possible to configure fall back link on the router if any one site goes down. Please let me know the steps to configure.

Thanks

Abhishek

[Tommer Catlin]

Can you define fallback line?  Are you talking about redudant WAN links?  SRST?  PSTN?

If you have CUCM, and the site has an ISR router, you can configure SRST for fall back.  This means if the WAN link drops, the site's phones will register to the SRST router and continue to work with limited funcationality and features.  They will have access to the local PSTN circuits or lines configured on the router.

If you are looking for fall back from a PRI T1 connection, configure in CUCM multiple Route Patterns or at the router, dialer Peers in the correc order you want to use for different T1s or FXO ports

[abhishekbanik]

Hi Tommer,

Iam talking about the WAN link going down and falling back to another ISR router. Its just like SRST , when the WAN links goes down one site should register register to SRST router.

Can you provide me configuration steps that can be done on the SRST router so that PRI works normally.

Thanks

Abhishek

[Tommer Catlin]

Here is the SRST guide for you.

http://www.cisco.com/en/US/docs/voice_ip_comm/cusrst/admin/srst/configuration/guide/srst41/srst41sa.html

Basically, you need to configure CUCM for this site (SRST)

Apply the SRST Site to the Device Pool

Configure the router for SRST

Reboot the phones so they are aware of the new SRST router

Setup the dial peer you want to use for dialing inbound or outbound or both. Simply using 9T usually is fine for outbound, prioritize 911 and9911 of course

Inbound, you will need to normalize or strip digits if you have 4 digits extensions, otherwise when the call comes inbound, its 10 digits and the router will not know what to do with it.

Voicemail rollover is complicated and sometimes not needed

Remember, SRST fallback and then re-registration to CUCM takes a few minutes. Its not immediate. So be patient in your testing until you are familiar with SRST

Good luck!