Cisco 3750 connected via trunk and PO6 to a core (all SFP) stack 4 but core side links are all Solid Amber

[m-abooali]

Hi guys,

I just added a stack two Cisco 3750G to a stack 4 Cisco 3750 (All SFPs) via trunk and port-channel. Po6

configuration seems to be correct as I have 7 other stacks connected in same manner.

at the core side all links are Solid Amber. sh int 1/0/6 through 4/0/6 are solid Amber. up links at the stack of two Cisco 3750G are Green.

at the core side, sh int gi1/0/6 - 4/0/6 are up line protocol down (suspended). seems like Spanning tree but show commands do not show any indication if blocking!?

any help/suggestions would be greatly appreciated folks.

have checked:

VTP ver 3, domain, mode, pass at both sides found no issues.

core is primary VTP master and all nodes are transparent mode

Best Regards,

Best Regards,

Masood

Masood

[m-abooali]

hello again,

resolved it.

I remove the Po6

remove po6 from interfaces

shut interfaces

added channel-group 6

no shut

these were done at the core (all sfp stack of 4 3750s)

these steps fixed the problem.

thank you all.

Best Regards,

Masood

[m-abooali]

Hello again,

resolved.

at core side,

removed po, shut interfaces,

recreated and add PO under interfaces

no shut

these steps resolved it.

Best Regards,

Masood

[Georg Pauwen]

Hello,

--> core is primary VTP master and all nodes are transparent mode

Check if that is really how your switches are configured, why would all the nodes be in transparent mode ?