Solved: Re: LAN Computers Always Disconnect Every 10 Minutes!

Ralph Rankin · ‎01-08-2013

Hi Experts,

i'm newbie in a cisco switch and i need help or advice how to fix this problem.

i'm using 2960 cisco switch and every department has a switch same model, i have noticed that every 10 to 15 minutes my network is disconnected for atleast 10 seconds and all client conneted to the server was disconnected also. please help how to fix this...

Thanks..

Ralph

Netadmins_BNPP2K10 · ‎01-11-2013

Hello,

Could you please input the command "sh spanning-tree vlan 1 detail" in each switch and show us the output ?

View solution in original post

shamax_1983 · ‎01-13-2013

Hello Raffy,

Is this your Core switch ?

Looks like you have some looping in your network.

What is plugged in to port FastEthernet0/12 ?

If you can, unplug the device and see how the network behaves.

If it is another production switch, do "sh spanning-tree vlan 1 detail" and post the results. If it is not a Cisco switch, check for any physical loops on the ports.

Let me know what you find.

Please don't forget to rate useful posts..

Shamal

View solution in original post

shamax_1983 · ‎01-14-2013

Hi,

Check each port on that switch. Look for any physical loops. Also make sure this switch has STP turned on ( You should find the setting somewhere in the GUI )

At this point ( based on your earlier post ) your STP root is the SG switch. This should not be the case. With your Topology, your STP root should be your core switch.

In Core switch's CLI, Add the following command in global configuration mode

!
spanning-tree vlan 1 root primary
!

This should make your core switch the root.

After that leave it for about 1 hour and post another "show spannig-tree vlan 1"

Shamal

Sent from Cisco Technical Support iPhone App

View solution in original post

Leo Laohoo · ‎01-08-2013

Can you clarify further? Are you saying that ALL computers disconnect every 10 to 15 minutes or this issue is observed to SOME computers.

Ralph Rankin · ‎01-08-2013

yes sir all computer accessing to the server was diconnect and then resume after 10 seconds. im using Cisco Network Assistant to figure out some errors, ived found that 1 switch has FCS errors 1059 total and Collision Frament 110 total and still increasing, what is this means sir? thanks

shamax_1983 · ‎01-08-2013

Hello Raffy,

If you know how to check the CPU utilization of your switches, Can you please let us know the number for each switch..

Also can you check your core switch's up-time and let us know ?

Thanks

Shamal

Ralph Rankin · ‎01-08-2013

Core Switch

CPU Utilization = 4%

Memory = 29%

SW1

CPU Utilization = 4%

Memory = 28%

SW2

CPU Utilization = 5%

Memory = 28%

SW3

CPU Utilization = 14%

Memory = 64%

thats all sir.

Leo Laohoo · ‎01-09-2013

Ok Raffy, few more questions.

When you say ALL computers get disconnected, did you detect a pattern? Like all computers connected to one physical switch getting disconnected?

shamax_1983 · ‎01-09-2013

In addition to leolaohoo's question, Can you get the uptime of each switch using Network Assistant or may be do a "show version" for each switch and post the outputs ( If you have CLI access )?

Ralph Rankin · ‎01-09-2013

@Sir leolaoho the ALL computer accessing the server is in deffirent switches. i do ping for monitoring the different switches inlude some clients where they belong, but also same result disconnect all of them at the sametime. ived tried also to connect direcly to core switch but same result ived got..

@Sir Shamai

ived recently purchase this 3 switches with same version and model. but i will check to post here. thanks..

Ralph Rankin · ‎01-09-2013

Additional Info.

Device Type - WS-c2960-24TC-S

Current Version - 12.2(50)SES -CRYPTO (On 3 Switches)

Current Version - 12.2(55)SE5 - LAN-BASE-CRYPTO (1 Switch)

shamax_1983 · ‎01-09-2013

Hi Raffy,

I asked for the "show version" because it gives you the uptime of the switch. Can you check the uptime of the each switch, this way we can make sure none of them are crashing.. and we can rule that out..

Ralph Rankin · ‎01-09-2013

Hi Shamal,

here is the show version if different switch.

rdrdcswitch1>show version

Cisco IOS Software, C2960 Software (C2960-LANLITEK9-M), Version 12.2(50)SE5, RELEASE SOFTWARE (fc1)

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

Compiled Tue 28-Sep-10 13:44 by prod_rel_team

Image text-base: 0x00003000, data-base: 0x01200000

ROM: Bootstrap program is C2960 boot loader

BOOTLDR: C2960 Boot Loader (C2960-HBOOT-M) Version 12.2(44r)SE4, RELEASE SOFTWARE (fc1)

rdrdcswitch1 uptime is 2 days, 1 hour, 3 minutes

System returned to ROM by power-on

System image file is "flash:c2960-lanlitek9-mz.122-50.SE5/c2960-lanlitek9-mz.122-50.SE5.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.

cisco WS-C2960-24TC-S (PowerPC405) processor (revision N0) with 65536K bytes of memory.

Processor board ID FCQ1612X2KA

Last reset from power-on

1 Virtual Ethernet interface

24 FastEthernet interfaces

2 Gigabit Ethernet interfaces

The password-recovery mechanism is enabled.

64K bytes of flash-simulated non-volatile configuration memory.

Base ethernet MAC Address : 5C:50:15:AA:43:80

Motherboard assembly number : 73-11472-10

Power supply part number : 341-0097-03

Motherboard serial number : FCQ16110MWK

Power supply serial number : DCA160780YZ

Model revision number : N0

Motherboard revision number : A0

Model number : WS-C2960-24TC-S

System serial number : FCQ1612X2KA

Top Assembly Part Number : 800-29857-05

Top Assembly Revision Number : C0

Version ID : V07

CLEI Code Number : COMCV00ARB

Hardware Board Revision Number : 0x01

Switch Ports Model SW Version SW Image

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

* 1 26 WS-C2960-24TC-S 12.2(50)SE5 C2960-LANLITEK9-M

Configuration register is 0xF

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

rdrdcswitch2>show version

Cisco IOS Software, C2960 Software (C2960-LANBASEK9-M), Version 12.2(55)SE5, RELEASE SOFTWARE (fc1)

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

Compiled Thu 09-Feb-12 19:11 by prod_rel_team

Image text-base: 0x00003000, data-base: 0x01900000

ROM: Bootstrap program is C2960 boot loader

BOOTLDR: C2960 Boot Loader (C2960-HBOOT-M) Version 12.2(53r)SEY3, RELEASE SOFTWARE (fc1)

rdrdcswitch2 uptime is 2 days, 1 hour, 11 minutes

System returned to ROM by power-on

System image file is "flash:/c2960-lanbasek9-mz.122-55.SE5/c2960-lanbasek9-mz.122-55.SE5.bin"