Cat 6500 Sup2T-10G-XL Max Virtual Ports Per Line-Card

[dankidd09]

Im in the process of planning an upgrade from 3750G to 6504 VSS pair as we have hit the STP instance limit on the 3750G's.

Im trying to understand the STP limitation of the Cat 6500 running Sup2T with IOS15.2 as I seem to have read there is no chassis limit as such more a module limit of approx 1800 virtual-port PVST instances. If as planned I want to run a 6748-SFP card with a 1800 module limit then if all ports are connected, I calculate this to mean I can only run a max of approx 37 vlans per port before I hit the limit? This seems a little low to me??

Ive scoured the web for any upto date documentation but nothing recent than confirms the limitations. Can anyone help me out here and confirm 6500 / Sup2T virtual port limitations in my planned configuration?

Many thanks

[Reza Sharifi]

The limit is for the whole chassis and sup.  The max number of supported vlan is 4096.

HTH

[dankidd09]

Thanks for your reply Reza. What I would like confirming is the max number of virtual ports you can run. Ive found old literature which states the chassis can handle PVST 12000+ virtual ports and 1800 per line card with 1 virtual port being I pvst instance per port. If all ports are active then this means I could only trunk a max of 37 vlans per port. It should be enough for my needs but I would like to clarify so I can be sure of limitations of the chassis if expanded in the future.

[Reza Sharifi]

Hi,

When you say "virtual ports" you mean vlan?

Are you planning to put each port in a separate vlan?

Can you explain what you are trying to do?

here is the data sheet for sup-2T

https://www.cisco.com/c/en/us/products/collateral/interfaces-modules/catalyst-6500-series-supervisor-engine-2t/data_sheet_c78-648214.html

Thanks,

[dankidd09]

By virtual port I mean STP/VLAN instance per port. As I understand the CAT6500 doesn't directly limit the number of STP instances. It has limits on the number of virtual ports per line card. A virtual port is a VLAN being forwarded on a trunk. So if you have 10 VLANs and 5 active trunks with no pruning then you have 50 virtual ports.

A 6500 chassis on old SX IOS is limited to 1800 virtual ports per line-card. For a 48-port line card with all 48 ports used using PVST+ this equates on average to 37 VLANs maximum per port before hitting the limit. Manually pruning VLANs may be required.

Some of the 6500 IOS versions have removed the virtual port limit on the newer line cards (6500 and 6700 series), however the per-chassis limits still apply. Ive read the per-chassis limits are 12000 for RPVST+ and 15000 for PVST+ but cant find info on line card / module limits.

[July sall]

did you find the info you needed? about the virtual port limitation

i read this too

https://www.cisco.com/c/en/us/td/docs/solutions/Enterprise/Data_Center/DC_Infra2_5/DCInfra_5.html

https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst6500/ios/12-2SX/release/notes/ol_14271/overview.html#wpxref22992

https://supportforums.cisco.com/t5/lan-switching-and-routing/maximum-spanning-tree-instances-128/td-p/2229016