cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
13967
Views
0
Helpful
1
Replies

Disabling keepalive in switch

Jerald Simon M.
Level 1
Level 1

         If i am disabling keepalive in switch port , is it  create any issue on network.

below issue we are facing....

connectvity :- 2 access layer switch connecting to 1 normal server

error : below loggs i m  getting on one of the switch and both switch interface going down (errordisable)

%ETHCNTR-3-LOOP_BACK_DETECTED: Keepalive packet loop-back detec

%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernetx/x

is there any solution for this ?, most of the forum saying disable keepalive in interface level and check physical cabling part.

1 Reply 1

InayathUlla Sharieff
Cisco Employee
Cisco Employee

https://supportforums.cisco.com/docs/DOC-3876

  http://raabadnetworking.blogspot.in/2010/01/ios-ethcntr-3-loopbackdetected.html

IOS: %ETHCNTR-3-LOOP_BACK_DETECTED : Keepalive packet loop-back detected on [chars]

Description

The problem occurs because the keepalive packet is looped back to the port that sent the keepalive. Keepalives are sent on the Catalyst switches in order to prevent loops in the network. Keepalives are enabled by default on all interfaces. You see this problem on the device that detects and breaks the loop, but not on the device that causes the loop.


Workaround


Issue the

no keepalive

interface command in order to disable keepalives. A disablement of the keepalive prevents errdisablement of the interface, but it does not remove the loop.


Permanent Fix


In Cisco IOS Software Release 12.2(x)SE-based releases and later, keepalives are not sent on fiber and uplink interfaces by default. Upgrading the IOS version to this or later images should prevent the above issue in the first place.

Review Cisco Networking for a $25 gift card