[nsp] policy routing / CEF-IP-POLICY: fib for address10.209.254.254 is with flag 0

[Tim Franklin]

cisco-nsp-bounces at puck.nether.net wrote:

> Any other suggestions to sort this out:
> 
>   10.209.0.0/24 -> via ISDN, if available, X/Y/Z otherwise
>   10.209.1.0/24 -> via X/Y/Z, if available, ISDN otherwise
> 
> are welcome.

When the policy routing fails, do the packets get forwarded on the path the routing table suggests, or are they dropped?

If they're forwarded, how about:

- Set up 'standard' routing by whatever means you see fit, so that the default path between A and B is A->X->Y->Z->B, and that A->ISDN->B is used if that route's unavailable.  (ie prefer the path-of-many-hops to the route via the directly connected interface, so some form of metric frobbing required.)

- Policy-route from 10.209.0.0/24, set next-hop of the ISDN interface on B, which *is* directly connected

ie do the flip side of what you're trying to do now and "special case" the delay-sensitive traffic instead of the bulk traffic.

Delay sensitive packets will hit the policy, and try to be sent over the ISDN.  If the ISDN's down, the policy routing will fail, and they'll be sent via whatever's in the routing table, which should be X->Y->Z.

Bulk packets will miss the policy and follow the routing table, by default X->Y->Z.  If that's down, they'll follow the backup route across the ISDN.

Regards,
Tim.

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Tim Franklin          ____________
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