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Setting routes w/ set next hop verify-availability in IOS 12.2

I'm trying to set up a 6509 switch with a MSFC2 card to route based on the reachability of one of two outbound routers. I've set up this sort of thing using:

ip sla monitor 1 type echo protocol ipicmpEcho 10.100.20.5 frequency 15

ip sla schedule 1 start-time now life forever

track 1 rtr 1 reachability

ip route x.x.x.x 255.255.255.255 10.100.20.5 track 1

on routers that have IOS 12.3 or later. What I'm doing is monitoring

10.100.20.5 with pings, and if the pings work, I'm adding a static route for a particular host pointing to 10.100.20.5. If the ping fails, then the static route is remove and the host uses whatever entry is in the routing table. I've used this approach before successfully.

Unfortunately, the version of IOS available for the MSFC2 tops out at

12.2, so I can't use this particular solution.

I've come across an older tracking method that is compatible with

12.2, but I'm not sure about its behavior. This is what I've found:

track 123 rtr 1 reachability

interface vlan0 ip address 10.100.30.1 255.255.255.0 ip policy route-map alpha

route-map alpha permit 10 match ip address "ACL-Including-x,x,x,x" set ip next-hop verify-availability 10.100.20.5 10 track 123

rtr 1 type echo protocol ipIcmpEcho 10.100.20.5 rtr schedule 1 life forever start-time now

I think that will do what I want, setting the next hop for that particular host if there is a good ping to that specific outbound router. What I'm not clear on is, what happens if the ping fails? Will the host then just use whatever route is in the MSFC2's routing table, or will it not have any route at all and the packets from the host just drop?

Thanks in advance.

Reply to
ttripp
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The route map will override the normal routing for that subnet. If the sla monitor says that the router is available then it set the next-hop to

10.100.20.5, otherwise it will send it to where the routing table says it should go. I'm curious as to what you are trying to accomplish. Why aren't you running a routing protocol on 10.100.20.5 or just using a static or floating-static route?
Reply to
Thrill5

I'm trying to load-balance voice/video traffic across multiple MPLS connections and 7200 routers running OSPF without getting into BGP. Using sla will let me point specific videoconferencing units out specific routers, while letting those same units fail over to using the OSPF routing table if a specific MPLS connection goes down. It's a bit convoluted, but BGP would be even more convoluted.

Of course, if you've got a better solution, I'd sure like to hear it.

Reply to
ttripp

ttripp schrieb:

You can do this with route-map too, but in a more shoot-yourself-in-the-foot manner.

Reply to
Uli Link

Well, that brings me back to the original post. Is that sort of tracking available in 12.2? I don't just want to track the interface on the local router (or routing switch, in this case), but out across my MPLS network.

Reply to
ttripp

Well, that brings me back to the original post. Is that sort of tracking available in 12.2? I don't just want to track the interface on the local router (or routing switch, in this case), but out across my MPLS network.

Doing this with BGP would be much easier. You could redistribute the desired routes into OSPF, using a route-map. The route-map is used to specify which routes would get redistributed into OSPF. I'm sure there are other simpler solutions to your problem, but without more details it's hard to tell you what they are. The solution you have come up with is very complicated, and like killing a fly with a sledge hammer.

Reply to
Thrill5

ttripp schrieb:

nope.

12.3T or better use 12.4 mainline.
Reply to
Uli Link

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