Switchport dies after host drops and comes back online

Unanswered Question
Aug 16th, 2007

We are running a 4507R SupII+ switch with WS-X4548-GB host modules. After a host reloads and comes back online, the switchport dies. Attempting to shut/no shut the port, the following message is logged:

Aug 15 15:32:14.164 UTC: %C4K_SWITCHMANAGER-4-S2WERRORREPORT: PimEthAutoNeg: S2w Read/Write Error for port Gi4/25.

This happens on all switchports within this module only. The only way to recover the port is to disable inline power with the power inline never command. I have searched for a bug in this version 12.2(25)EWA4 relating to this and have found nothing.

Should I be suspecting a switch module failure?

I have this problem too.
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I've had a similiar situation but ports were connected to routers. Mine is also 4507R w/ Sup V 10GE with WS-X4548-GB. The only way the ports would come back up was to set the speed to 100.

I came to a conclusion that since CAT-5 cable pin outs are different for 1000 and 10/100 (1000 also uses pins 4578) it couldn't auto negotiate thus the port remained down until I configured the port speed to 100.

This seems like a software bug.


m-sherman Thu, 08/16/2007 - 10:28

John...thanks for the reply.

I did locate a bug that documented a similar issue with 12.2(20) code. Bug ID CSCef87815 but I'm running 12.2(25).....

Pavel Bykov Thu, 08/16/2007 - 10:38

Since it seems like the problem is with autonegotiation, workaround would be to manually set speed and duplex, as suggested.

m-sherman Thu, 08/16/2007 - 10:43

Tried that initially with no resolve. The "inline power never" is the trick.

d-simic Thu, 08/23/2007 - 04:06

Hi, here's what cisco says:



This DDTS is basically a hardware issue that has been resolved by some

rework of the linecards.

Regarding to WS-X4548-GB-RJ45V, linecards with hw rev >= 2.2 are NOT


There is no software fix and affected cards should be replaced.


Can you post a "sh mod" of your switch?


m-sherman Thu, 08/23/2007 - 04:41

Chassis Type : WS-C4507R

Power consumed by backplane : 40 Watts

Mod Ports Card Type Model Serial No.


1 2 Supervisor II+ 1000BaseX (GBIC) WS-X4013+ JAE1043E867

3 48 10/100/1000BaseT (RJ45)V, Cisco/IEEE WS-X4548-GB-RJ45V JAE1043E8BK

4 48 10/100/1000BaseT (RJ45)V, Cisco/IEEE WS-X4548-GB-RJ45V JAE1048FXA2

6 48 10/100/1000BaseT (RJ45)V, Cisco/IEEE WS-X4548-GB-RJ45V JAE1120HP4S

M MAC addresses Hw Fw Sw Status


1 0019.aa4e.f6c0 to 0019.aa4e.f6c1 4.2 12.2(20r)EW1 12.2(25)EWA4 Ok

3 0019.e788.27f0 to 0019.e788.281f 3.1 Ok

4 001a.2f36.e200 to 001a.2f36.e22f 3.1 Ok

6 001b.d400.acb0 to 001b.d400.acdf 3.3 Ok

Mod Redundancy role Redundancy mode Redundancy status


1 Active Supervisor Non redundant Active

Card 4 has the issue

Card 3 seems unaffected

Card 6 is a planned replacement of card 4 which is also unaffected.


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