here is the link
also, you can access the following link and check all supported features per platform or IOS Version
Was told this last week regarding Stackwise Virtual Links on Cat 9500 and 9400
9500 SVL support is expected in 16.8.1 which should be on CCO towards end of this month. It will support StackWise Virtual (SVL) on 10G and 40G links for all 9500. However, SVL connections will not initially be supported on the uplink module. This should get enabled in a later release.
9400 chassis Stackwise-virtual (which offers the functionalities as VSS) is currently targeted with 16.9 release with single supervisor. Support with dual-supervisor is under consideration.
There’s an update from cisco, now SVL (a.k.a VSS) support on cat9400 series.
the thinks that make me confused last time was they said minimum supervisor C9400-SUP-1XL required, and now they said both Supervisor 1 Module (C9400-SUP-1) and Cisco Catalyst 9400 Series Supervisor 1XL Module (C9400-SUP-1XL) support SVL..
StackWise Virtual Link (SVL) connection “only through 10G or 40G uplink ports on the supervisor module (You cannot establish an SVL using a 10G port on one switch and a 40G port on the other switch.)”
Fast Hello Dual-active detection is supported only on supervisor module ports.
Hope this information helps.
I just got an update from Cisco,
Regarding the support of StackWise virtual on modular Catalyst 9400, it is going to be supported in the next release of IOS XE 16.9.1 targeted in July 2018. Please note, to support this, you would need to have new supervisors SUP-1XL as the previous generation of supervisor was targeted for the access layer, hence no HA like in collapsed core was not needed that time.
Is there a technical reason for not supporting SVLs with uplink modules at FCS? Can Cisco share a roadmap of which version IOS-XE that uplink modules will be supported? We purchased 9500-16X with 40G uplink modules and would like to use the 40G as the SVLs, but now are forced to drop down to last 10G ports.
Do C9410R support VSS ?
According to the Release Notes for 16.9.1 (LINK), StackWise Virtual is supported only on 9404R & 9407R chassis:
Cisco StackWise Virtual is a network system virtualization technology that pairs two switches into one virtual switch to simplify operational efficiency with a single control and management plane.
The feature is supported only on these chassis models and supervisor modules:
C9400 and C9500 are supporting StackWise Virtual: https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst9500/software/release/16-6/configuration_guide/b_166_ha_9500/b_166_ha_9500_chapter_01.pdf