cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
11919
Views
0
Helpful
4
Replies
snallncmec
Beginner

3750 Stack port issue

Hello,

I am provisioning a new 3750 switch stack (ip x.x.x.200) to replace an old stack (ip x.x.x.100).  I'm having issues with the stack-ports on the new stack.  Both stacks are 3750-E 48 ports (all switches in each stack are the same hardware running the same IOS code).  My SNMP monitoring is showing stack ports 1-2 and 2-1 as down, so I'm investigating.  Below (at the bottom..."SHOW OUTPUT") you find the output from the commands "show switch stack-ports summary", "show switch", and "show version".  I've tried disabling and reenabling the stack ports with:

switch 1 stack port 2 disable

switch 2 stack port 1 disable

switch 1 stack port 2 enable

switch 2 stack port 1 enable

but (with console logging) I get the following:

000138: *Mar  1 08:17:14.052 EST: % Disabling stack port not allowed with current stack configuration.

000139: *Mar  1 08:17:34.150 EST: % Disabling stack port not allowed with current stack configuration.

I've also tried reseating the stacking cable between 1-2 and 2-1 and even replacing it with a brand new stacking cable entirely, but get the same switch stack-ports summary.  It seems the problem is with port 2-1, but I can't find the stack-port summary trouble shooting for the combination of output shown (link OK = NO, Link Active = NO, but Sync OK = Yes).  It looks like both 2-1 and 1-2 are SENDING valid stacking protocol messages (Sync OK = Yes), but for some reason 2-1 is not receiving valid messages (LinkOK = No).  See "http://www.cisco.com/en/US/docs/switches/lan/catalyst3750x_3560x/software/release/12.2_55_se/configuration/guide/swstack.html#wp1277038"

So I'm stumped!  How can I get both stacking links working properly?

Thanks,

Sue

<<<<<<<<<<<<<<<<< SHOW OUTPUT >>>>>>>>>>>>>>>>>>>>

ServTierSw1#show switch stack-ports summary

Switch#/  Stack   Neighbor   Cable    Link   Link   Sync      #          In 

Port#      Port                  Length    OK   Active   OK    Changes    Loopback

               Status                                                         To LinkOK         

--------      ------        --------    --------      ----      ------  ----      ---------       --------

  1/1        OK         2          50 cm     Yes   Yes    Yes        2          No

  1/2        Down      None    50 cm     Yes    No     Yes       26         No

  2/1        Down      None    50 cm     No     No     Yes       24         No

  2/2        OK         1          50 cm     Yes   Yes    Yes        2         No

ServTierSw1#show switch

Switch/Stack Mac Address : a8b1.d4e5.6980

                                           H/W   Current

Switch#  Role   Mac Address     Priority Version  State

----------------------------------------------------------

*1       Master a8b1.d4e5.6980     15     1       Ready              

2       Member a8b1.d4e5.7200     10     1       Ready              

ServTierSw1#show ver

Cisco IOS Software, C3750E Software (C3750E-UNIVERSALK9-M), Version 12.2(55)SE1, RELEASE SOFTWARE (fc1)

Technical Support: http://www.cisco.com/techsupport

Copyright (c) 1986-2010 by Cisco Systems, Inc.

Compiled Thu 02-Dec-10 06:08 by prod_rel_team

Image text-base: 0x00003000, data-base: 0x02800000

ROM: Bootstrap program is C3750E boot loader

BOOTLDR: C3750E Boot Loader (C3750E-HBOOT-M) Version 12.2(44r)SE3, RELEASE SOFTWARE (fc3)

ncmec-ServTierSw1 uptime is 13 hours, 30 minutes

System returned to ROM by power-on

System image file is "flash:c3750e-universalk9-mz.122-55.SE1.bin"

This product contains cryptographic features and is subject to United

States and local country laws governing import, export, transfer and

use. Delivery of Cisco cryptographic products does not imply

third-party authority to import, export, distribute or use encryption.

Importers, exporters, distributors and users are responsible for

compliance with U.S. and local country laws. By using this product you

agree to comply with applicable laws and regulations. If you are unable

to comply with U.S. and local laws, return this product immediately.

A summary of U.S. laws governing Cisco cryptographic products may be found at:

http://www.cisco.com/wwl/export/crypto/tool/stqrg.html

If you require further assistance please contact us by sending email to

export@cisco.com.

License Level: ipbase

License Type: Permanent

Next reload license Level: ipbase

cisco WS-C3750E-48TD (PowerPC405) processor (revision K0) with 262144K bytes of memory.

Processor board ID FDO1424Z042

Last reset from power-on

3 Virtual Ethernet interfaces

1 FastEthernet interface

104 Gigabit Ethernet interfaces

4 Ten Gigabit Ethernet interfaces

The password-recovery mechanism is enabled.

512K bytes of flash-simulated non-volatile configuration memory.

Base ethernet MAC Address       : A8:B1:D4:E5:69:80

Motherboard assembly number     : 73-11175-14

Motherboard serial number       : FDO142412MU

Model revision number           : K0

Motherboard revision number     : A0

Model number                    : WS-C3750E-48TD-S

Daughterboard assembly number   : 800-29737-01

Daughterboard serial number     : FDO14240T9F

System serial number            : FDO1424Z042

Top Assembly Part Number        : 800-28920-03

Top Assembly Revision Number    : A0

Version ID                      : V04

CLEI Code Number                : COMCD00ARA

Hardware Board Revision Number  : 0x00

Switch Ports Model              SW Version            SW Image                

------ ----- -----              ----------            ----------              

*    1 54    WS-C3750E-48TD     12.2(55)SE1           C3750E-UNIVERSALK9-M    

     2 54    WS-C3750E-48TD     12.2(55)SE1           C3750E-UNIVERSALK9-M    

Switch 02

---------

Switch Uptime                   : 13 hours, 30 minutes

Base ethernet MAC Address       : A8:B1:D4:E5:72:00

Motherboard assembly number     : 73-11175-14

Motherboard serial number       : FDO142412LB

Model revision number           : K0

Motherboard revision number     : A0

Model number                    : WS-C3750E-48TD-S

Daughterboard assembly number   : 800-29737-01

Daughterboard serial number     : FDO14240UHY

System serial number            : FDO1424Z05V

Top assembly part number        : 800-28920-03

Top assembly revision number    : A0

Version ID                      : V04

CLEI Code Number                : COMCD00ARA

License Level                   : ipbase

License Type                    : Permanent

Next reboot licensing Level     : ipbase

Configuration register is 0xF

ServTierSw1#

4 REPLIES 4
p.mcgowan
Participant

it is possible you have a faulty stack port on one of the switches.

have you tried connecting stack 1/1 to stack 2/1 and 1/2 to 2/2 to see if the fault stays with port 2/1 or 1/2?

I have not, since we have servers connected to that and to do so would bring down the uplink for the top switch (since only the 1 stacking link is active)  But I can probably test it early in the morning.

Also, the stack had been up with no issues at all for a couple of days.  Switch 2 had been the master (it is not currently) when yesterday afternoon, my coworker unplugged the power cord of the master (bottom or switch 2) and re routed the power cord.  Pretty sure he did not touch the stacking cables, but could a problem develop from turning off the master in the stack?  When I saw the alert, which began right after he did that, the stacking link was reporting an issue.  I noticed that 2 was the master, and changed it (switch 1 priority 15, wr mem, reload) then since I usually like the top switch to be master - makes things neater. This morning some servers have been moved to the new stack with the stacking issues, so now it's harder just to reload or change the switch without causing service interruptions.  *sigh*

I finally found

http://www.cisco.com/en/US/docs/switches/lan/catalyst3750/software/troubleshooting/switch_stacks.html#wp39498

which indicates troubleshooting steps. 

I found that the cable on switch 2 side, was not tightened evenly.

Now I have:

ServTierSw1#sho switch stack-ports summ

Switch#/  Stack   Neighbor   Cable    Link   Link   Sync      #         In 

Port#     Port              Length    OK   Active   OK    Changes   Loopback

          Status                                          To LinkOK         

--------  ------  --------  --------  ----  ------  ----  ---------  --------

  1/1     OK         2      50 cm     Yes    Yes    Yes        2        No

  1/2     OK         2      50 cm     Yes    Yes    Yes       51        No

  2/1     OK         1      50 cm     Yes    Yes    Yes       49        No

  2/2     OK         1      50 cm     Yes    Yes    Yes        2        No

ServTierSw1#

Thanks!