Solved: Catalyst 2960G all ports going down when one port goes down!

gkonheiser · ‎07-22-2010

Hi There

I have a 2960G and a 3548XL. They are linked via a giga module in port Gi 0/2 in the 3548XL that runs into port Gi 0/6 into the 2960G. Since this morning the link has been going down, which is a problem, but whats more of a problem is that it takes down all the other ports on the 2960G for a while, ( they turn orange and then come back up Green when port 0/6 is back). My question is what could be causing all ports to go down?

thanks for your help in advance.

Nagaraja Thanthry · ‎07-22-2010

Hello,

Seems like all your ports are participating in Spanning-tree calculations

when there is a link state change. That is the reason you will see all ports

going orange and becoming green again. This is normal for trunk ports but

regular access ports (connected to workstations) need not participate in the

Spanning-tree. Please configure "spanning-tree portfast" under all

interfaces.

Interface range fa 0/1-24

Spanning-tree portfast

Or

Interface

Spanning-tree portfast

Hope this helps.

Regards,

NT

Note: Please rate helpful posts.

View solution in original post

Nagaraja Thanthry · ‎07-22-2010

Hello,

Seems like all your ports are participating in Spanning-tree calculations

when there is a link state change. That is the reason you will see all ports

going orange and becoming green again. This is normal for trunk ports but

regular access ports (connected to workstations) need not participate in the

Spanning-tree. Please configure "spanning-tree portfast" under all

interfaces.

Interface range fa 0/1-24

Spanning-tree portfast

Or

Interface

Spanning-tree portfast

Hope this helps.

Regards,

NT

Note: Please rate helpful posts.

gkonheiser · ‎07-23-2010

Your a star. Thank you very much problem solved. : )