Quad VSS support as two SUP running in each 6509E chassis

[shekharsaurabh2389]

Hi Team Customer is having 2 chassis of 6509-E and have dual sup 2T in each of the chassis. Now customer want that all the four SUP 2T should be part of VSS. Is this scenario possible because as per Cisco documentations "VSS mode does not support supervisor engine redundancy within a chassis.” However the below links also talk about the "VSS Quad-Sup Up link Forwarding". which contradicts with the above statement. https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst6500/ios/15-1SY/config_guide/sup2T/15_1_sy_swcg_2T/virtual_switching_systems.html

Below are the details of the existing setup.

• Currently core is running HSRP for redundancy
• Device current IOS is -- ipservicesk9_npe-mz.SPA.154-1.SY4.bin
• Currently two no. of SUP cards (VS-SUP2T-10G) is running in each chassis.
• Quad VSS support is from 15.1(1)SY1.

[Mark Malone]

Hi
originally there was no interchassis support in quad VSS so secondary sup went to rommon automatically , thats been changed in newer releases , ports act now same as single chassis with dual sups , secondary sup can use its uplinks

[shekharsaurabh2389]

Thanks Mark, it means that i can configure all the four sups as part of VSL and they can work in primary and secondary within chassis and inter chassis.

[Mark Malone]

There fully functional so in theory it should work but i have not tested it , there maybe a limitation too on the supervisor whether that can happen

see this in the doc you posted under restrictions
VSS mode does not support supervisor engine redundancy within a chassis.

[Giuseppe Larosa · Accepted solution]

Hello,

to take advantage of the feature Quad Sup VSS uplinks you need to follow an interconnection schema that has one VSL link between each possible pair of supervisors. Additional VSL links taken from linecards can be added if needed.

see the whitepaper below

https://www.cisco.com/c/dam/en/us/products/collateral/interfaces-modules/network-modules/white_paper_c11_429338.pdf

on page 15 there is a figure and explanation

© 2012Cisco and/or its affiliates. All rights reserved. This document is Cisco Public Information.Page 15of 55Figure 8. Quad-Sup Uplink Forwarding

VSL Configuration

Quad-Sup Uplink Forwarding VSL design using all 10 Gigabit ports on the supervisor modules:

●Maintains 20 Gbps VSL bandwidth in the event of a supervisor failure

●Maintains at least one locally attached VSL port to the active supervisor, in the event of a supervisor module failure

●Requires no additional line cards

If additional bandwidth is needed for the VSL, additional 10 Gigabit ports from supported line cards can be used. Up to eight ports per port channel can be added, just like any other port channel interface.

Hope to help

Giuseppe

[shekharsaurabh2389]

Thanks Giuseppe for the insight, really appreciate the help.