cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
909
Views
15
Helpful
6
Replies

my 2960S has problem with VLANs

GH_Lee
Level 1
Level 1

hi. i use 2960S for test

but few days ago, VLAN interfaces got down and up intermittently.

so i looking for log about VLAN problem but there was nothing about information about this problem. just written like some vlan interfaces down and up.

is there bug about specific version of ios or just my device's problem?

if you guys know about this problem, help me.

1 Accepted Solution

Accepted Solutions

balaji.bandi
Hall of Fame
Hall of Fame

You have not mentioned how these switch connected in the network, is this standlone Switch or connect to Core/Distribution swithch ?

 

If it is standalone switch, how many devices connected. there may be reason VLAN Go Up and Down, there is no members in that VLAN port like no device connected, the interface VLAN go down, when the active device connected  then vlan come up.

 

nice to have show version and show interface status, show running config ( as suggested other post to understand envirionment)

 

BB

***** Rate All Helpful Responses *****

How to Ask The Cisco Community for Help

View solution in original post

6 Replies 6

Jaderson Pessoa
VIP Alumni
VIP Alumni
Maybe it is a stp problem. Could you provide a output from

show spanning-tree
show spanning-tree summary
show interfaces trunk
Jaderson Pessoa
*** Rate All Helpful Responses ***

thx for your help.

i'll tell these commands to original owner.

have a good day!

Deepak Kumar
VIP Alumni
VIP Alumni

Hi,

What is your switch IOS version?

 

There may some reasons behind the scene as STP issue with the network, Physical Link Flapping et. 

 

If the switch is not restarted yet  then share some output as "Show Logging", "Show Version", "Show spanning-tree active..."

 

Regards,
Deepak Kumar

 

Regards,
Deepak Kumar,
Don't forget to vote and accept the solution if this comment will help you!

this switch is now out of my hands so can't check about IOS version.

but there's only VLANxxx has up and down record. no reason.

anyway thx about your reply! have a good day!

balaji.bandi
Hall of Fame
Hall of Fame

You have not mentioned how these switch connected in the network, is this standlone Switch or connect to Core/Distribution swithch ?

 

If it is standalone switch, how many devices connected. there may be reason VLAN Go Up and Down, there is no members in that VLAN port like no device connected, the interface VLAN go down, when the active device connected  then vlan come up.

 

nice to have show version and show interface status, show running config ( as suggested other post to understand envirionment)

 

BB

***** Rate All Helpful Responses *****

How to Ask The Cisco Community for Help

it was used for infrastructure network but has problem. so i got it out for test.

i think VLANs are flapping. so i connected with other switch and it seems has problem.

there's no log about VLAN up and down reason. just recorded like VLANxxx has down or up.

thx for your reply!

 

Getting Started

Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community:

Innovations in Cisco Full Stack Observability - A new webinar from Cisco