IP SLA for EIGRP

[Jorge Alberto Largaespada Gonzalez]

Hi everyone,

I have the following topology with extended layer 2. i have all router with the same metric so all the router have two path to same destination. but what happen if the link between the two switch layer 2 goes down. all the router send round-robin or load balancing. so i need some advice with this i think that can i use IP SLA with PBR to minor the IP management on the layer 2 switch on the router, if the link goes down remove the route but i dont see any documentation about IP SLA to remove route with EIGRP. Can i use another method to accomplish this?

[rosannle · Accepted solution]

Hello Jorge,

This might be a bit of a stretch but have you considered using EEM (Embedded Event Manager)? This can be done on the 2 layer 2 switches.

I am making an assumption that the 2 servers connected to the 2 L2 switches are in different VLANs.

If so, you can configure EEM on both the L2 switches to monitor the port status of the link between them. If the interface goes down, you can set the switch to delete the VLAN accordingly. This should propagate to the L3 switches through VTP, thus deleting the VLAN there. This will cause the interface VLAN to go down on the L3 switches and the route for that network will not be advertised via EIGRP.

[Note: You should also make sure to monitor when the interfaces between the switches come back up to set the switches to create the VLAN accordingly as well.]

Here is an example:

Switch(config)#event manager applet TEST-Port-Down

Switch(config-applet)#event syslog pattern "Interface GigabitEthernet0/0, changed state to down"

Switch(config-applet)#action 1.0 cli command “enable”

Switch(config-applet)#action 1.0 cli command “configure terminal”

Switch(config-applet)#action 1.0 cli command “no vlan 10”

Switch(config)#event manager applet TEST-Port-Up

Switch(config-applet)#event syslog pattern "Interface GigabitEthernet0/0, changed state to up"

Switch(config-applet)#action 1.0 cli command “enable”

Switch(config-applet)#action 1.0 cli command “configure terminal”

Switch(config-applet)#action 1.0 cli command “vlan 10”

Switch(config-applet)#action 1.0 cli command “exit”

Hope this helps!

Rosanne

[Jorge Alberto Largaespada Gonzalez]

thanks a lot, you save my life.