EIGRP doubt

For discussions and questions related to Routing guides and labs on routeralley.com.

EIGRP doubt

Postby m1607 » Fri Jul 22, 2011 4:33 am


In eigrp with command sh ip eigrp topology summary
Just want to know meaning of term Head serial and next serial

Thanks for help in advance

Switch#sh ip eigrp 1 topology summary
EIGRP-IPv4 Topology Table Summary for AS(1)/ID(
Head serial 1, next serial 2
1 routes, 0 pending replies, 0 dummies
Enabled on 1 interfaces, 1 neighbors present on 1 interfaces
Quiescent interfaces:
Posts: 1
Joined: Wed Jul 20, 2011 9:59 pm

Re: EIGRP doubt

Postby aaronbalchunas » Sat Jul 23, 2011 9:37 am

Moved this topic to the Routing forum, as it relates to EIGRP.

There is not alot of information out there regarding your question. The clearest answer I can find is here on page 8:


"Serial" in this context does not refer to an interface, but rather a serial number identifying the EIGRP topology database revision number. I will assume that "head serial" refers to the first revision, and "next serial" refers to the current version (or perhaps the next revision, it's a little unclear). Any time a topology change occurs, the "next serial" number is incremented by one.

If this number is incrementing often, then your EIGRP domain is likely unstable.

- Aaron
Site Admin
Posts: 12
Joined: Sat Mar 26, 2011 3:46 pm

Return to Routing

Who is online

Users browsing this forum: Bing [Bot] and 1 guest