Trunking SG550XG with 6509

[KenArcher]

We have a 6509 with approximately 13 predefined VLANs that have been previously trunked down to our client access switches without issue. We recently installed an SG550XG, but are unable to trunk the ports correctly. Any help would be much appreciated.

Catalyst 6509:

CISCO6509#sh run int te2/16
Building configuration...

Current configuration : 102 bytes
!
interface TenGigabitEthernet2/16
description MDF-SG550-101
switchport
switchport mode trunk
end

SG550XG:

MDF-SG550-101#sh run int te1/0/24
interface TengigabitEthernet1/0/24
description CISCO6509
spanning-tree link-type point-to-point
switchport mode trunk
macro description switch
!next command is internal.
macro auto smartport dynamic_type switch
!

A show vlan on the SG550XG displays only the native vlan (1) and the vlans from the 6509 do not appear to be trunking down to the SG550XG.

[Seb Rupik]

Hi there,

Have you explicitly defined the VLANs on the SG550?

Cheers,

Seb.

[mridsing]

Hi,

Thanks for your post,

Kindly request you to open a case by calling our frontline team so that we can troubleshoot issue.
Frontline TAC link:-
https://www.cisco.com/c/en/us/support/web/tsd-cisco-small-business-support-center-contacts.html

->With the current network we need to check with vlan are been mapped in uplink port to 6509
->Same vlan in 6509 are also created in SG550XG
->Smartport needs to be disabled in our SG550XG.

Thanks,
Mridul
Cisco SBSC

[KenArcher]

It was my understanding than VLANs defined on the 6509 would pass down to adjacent switches when trunking is enabled. This is how it worked on previously deployed 2960S and 2960X switches. The idea of having to manually define the VLANs on every adjacent switch seems a bit cumbersome.

[KenArcher]

A show interface switchport display a Trunking VLANs: 1 and 2-4094 (Inactive). Manually defining VLAN 2 changed that to Trunking VLANs: 1-2 and 3-4094 (Inactive). And show vlan now shows VLAN 1 untagged on all ports and VLAN 2 tagged on the trunked ports. I haven't tested just yet, but VLAN 2 will probably pass without issue if I connect a client and tag it's port. However, I'm still wondering why the VLANs defined on the 6509 are not automatically defined on the the SG550XG when they are automatically defined on 2960 series switches.

[Seb Rupik · Accepted solution]

Are you running a VTP domain? This would explain why you didn’t have to manually configure the 2960 switches VLAN information. VTP pruning being enabled would also explain why it was sufficient to just configure switchport mode trunk with out explicitly defining the trunked VLANs.

The SG550X does not support VTP, but does GVRP. However I'm not sure on GVRP on support on the 6500. I think you may have to manually configure these switches.

cheers,

Seb.

[KenArcher]

Thanks, that does explain my confusion. It looks like the 6509 does support GVRP, but you can't use it as a VTP server with GVRP running on it. Another switch would need to be configured as the VTP server.