Like a nasty cockroach or slippery rodent on the subway track — bugs plague Cisco devices just as any other code out there (sorry Jeremy Cioara  — there ARE bugs!) lol

bed bug train



Yes, deep in those smelly tunnels are thos unspeakable pests! I’ve ran into a bunch of them in the past but I think I’ll start tracking them as I find them just since I’m sure others will run into them as well. Use the CATEGORY > BUGS to see if any of the titles makes sense for you — you might be looking at a bug!





Today’s blog post is bug # CSCub31212

N5k System restart due to “ipfib” hap reset.


I had a 5k of mine randomly reboot on me for some strange reason. Luckily the backup kicked in so we didn’t lose anything aside from a bunch of alerts coming in, but after looking at the logs I saw nothing except for logs within the past hour!


I looked at all BGP/EIGRP neighborships and saw that none of the adj broke except for the switch that rebooted. (use #sh ip eigrp nei and #sh ip bgp summ to see the time in how long a neighbor has been up for).

Next, I did a #sh system reset-reason

CORE-02# sh system reset-reason
—– reset reason for Supervisor-module 1 (from Supervisor in slot 1) —
1) At 43082 usecs after Mon Aug 25 13:53:09 2014
Reason: Reset triggered due to HA policy of Reset
Service: ipfib hap reset
Version: 5.1(3)N2(1a)

So for some reason this process caused the switch to reboot?

Google around didnt take me long to find said bug ID.

The leak is around 1.8-2MB per day which results in a crash after almost 130 days . (250MB is the limit) 

To identify the current memory allocation for ipfib process , please use the following command and check 
for MemAlloc. If you observe the MemAlloc is close to 250000000(250MB) you are on 
the risk of a crash .”


Basically its ticking time bomb. Fix is to upgrade the code to a newer version.



William Zambrano

William Zambrano

NYC networkers is run by William Zambrano, a passionate network engineer who has been in the IT industry for eight years who posts up blog articles, YouTube videos, and holds events in the NYC area. He lives in Queens, New York and has consulted in various different companies in the NY area. Previously William worked as a Cisco Certified Systems Instructor (CCSI) but now currently works for Arista Networks serving as a Systems Engineer. William can be reached by email at

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