Preview Tool

Cisco Bug: CSCus33161 - C2900:EHWIC-4ESG:doesn't forward traffic after STP topology change

Last Modified

Dec 13, 2018

Products (1)

  • Cisco 2900 Series Integrated Services Routers

Known Affected Releases

15.1(4)M9 15.5(1)T

Description (partial)

When a link is down on the EHWIC-4ESG/C2900 and stp topology change happens in the network,
traffic which was transmitted out from that port originally should be transmitted out from another port
on the EHWIC-4ESG after convergence,but not transmitted out.

And when the down link goes up again,even though MAC is flushed on the router,
the router continues to forward traffic to another port only(never flooding).

So,that traffic never reaches the destination because there is the stp blocked port on the path in the original stp topology. 

Then,in both cases,it is recovered by clear arp-cache on the router.

It is found on 15.1(4)M6 and 15.2(4)M7.

And it is seen on 15.5(1)T and 15.4(3)M1.
Bug details contain sensitive information and therefore require a 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.