Guest

Preview Tool

Cisco Bug: CSCuo08297 - PBR work abnormal with a summary route include set ip next-hop address

Last Modified

May 08, 2020

Products (1)

  • Cisco Catalyst 6000 Series Switches

Known Affected Releases

15.0(1)SY2

Description (partial)

Symptom:
1. In 150-1.SY2 IOS image customer configure PBR, the topology as following, both switch B and switch C have route to switch D, on switch A configure PBR through switch C to switch D, and switch C have a route through switch B to switch D network if not match. Normally source to destination(switch D) through switch A and match PBR through switch C to switch D. On switch A shut down the connection interface between switch C, find the traffic been drop, and find there's a summary null 0 route include the set next hop ip address. When remove the null0 route work well. And upgrade IOS image to 151-1.SY3, with null 0 route, the match traffic will loose half packets.

Source ------- switchA------------switchB-------|
                         |                                     |
                         |                                     |
               switchC------------------------------switchD


2. In IOS image 151-1.SY3 or 150-1.SY6 with null0 route shut down interface packet will be punt for software processing. There is 50% traffic loss.
Debug ip policy shows that one packet will be policy routed, which is dropped and the other will be normal route forwarded with success.

Conditions:
With a null0 route include set next-hop address; Or a summary route include next-hop address point to a up interface.
Bug details contain sensitive information and therefore require a Cisco.com account to be viewed.

Bug Details Include

  • Full Description (including symptoms, conditions and workarounds)
  • Status
  • Severity
  • Known Fixed Releases
  • Related Community Discussions
  • Number of Related Support Cases
Bug information is viewable for customers and partners who have a service contract. Registered users can view up to 200 bugs per month without a service contract.