Flapping routes for 1 subnet

[maryodriscoll]

Hi,I have 2 routers sitting on a shared lan with hsrp running between them. Hanging off this lan is another set of 2 switches with L3 blades running HSRP between the different sub-interfaces. HSRP is stable and has never gone down. When I check a route for 10.90.30.0 , i see 2 routes for it - via each respective switch. If I check the IP route for this particular subnet every 10seconds or so, it flaps back and forth. Does anyone know why this is happening ?

[Richard Burts]

Perhaps you could explain a little more about this situation. On which box are you seeing this symptom (or is it on all the boxes)? Is this subnet a directly connected subnet on any of the boxes? Is this subnet known via static route or via dynamic routing protocol (and if dynamic - which routing protocol)?

Also I am unclear exactly what symptoms you are experiencing. You say that if you show ip route for that particular subnet that you see two routes to it, and if you check again in 10 seconds it flaps - what do you mean about flapping?

HTH

Rick