StackWise Virtual – Prerequisites and Restrictions

We hope you have got an understanding of the StackWise Virtual, its benefits, architecture, and the components from our previous blog.

Now, if you want to deploy StackWise virtual in your IT environment then this blog will help you a lot in understanding the prerequisites, restrictions that should be kept in your mind before deploying StackWise Virtual.

In order to configure StackWise virtual, there are some prerequisites that need to be fulfilled.

  • StackWise Virtual consist of a switch pair and both the switches must fulfill the following conditions:
    • Connectivity must be direct between them.
    • The model must be the same for both switches.
    • Licenses must be the same for both switches.
    • The software version must be the same for both switches.
    • SDM Template must be the same for both the switches.
  • Ports present in StackWise Virtual Link (SVL) must be of the same speed. 40G and 10G ports cannot be merged together to form SVL. If you are using 10G Ports, bundle the required number of 10G ports and use it as an SVL but if using 40G link, bundle both the 40G and use it as SVL.

    Restrictions for Catalyst 9400 Switches
  • Models that support StackWise Virtual:
    • Cisco Catalyst 9404R
    • Cisco Catalyst 9407R
    • Cisco Catalyst 9410R
  • Supervisor modules that support StackWise Virtual:
    • Cisco Catalyst 9400 Series Supervisor 1 Module
    • Cisco Catalyst 9400 Series Supervisor 1XL Module (C9400-SUP-1XL)

* An additional C9400-SUP-UPG-LIC= license is required for SWV if you have Catalyst 9400 Series Supervisor 1 Module (C9400-SUP-1).

  • Only 10G or 40G uplink ports on the supervisor module can be used to form StackWise Virtual Link.
  • SVL can not be formed using a 10G port on one side switch and 40G on the other side.
  • Per chassis only one supervisor module can be used for configuring StackWise Virtual.
  • Two SUP modules can be installed in each chassis used in the SWV solution but only one SUP module will be active and the other will be powered off.
  • Fast Hello DAD is only supported on supervisor module ports. If you want to use DAD on line cards you will have to use Enhanced PAgP DAD as it supports Supervisor as well as line card ports.
  •  Catalyst 9400 does not support pre-provisioning.

Restrictions for Catalyst 9500 Switches

Below mentioned are the restrictions for Catalyst 9500 Switches.

  • Models that support StackWise Virtual:
    • C9500-24Q
    • C9500-12Q
    • C9500-40X
    • C9500-16X
  • StackWise Virtual Links cannot be created on any of the network modules on Cisco Catalyst 9500-40X and C9500-16X models.
  • The FIPS (Federal Information Processing Standards) is not supported on Cisco StackWise Virtual links.
  • With SVLs 4x10G breakout cables are not supported.

Restrictions for Catalyst 9600 Switches

Here are the restrictions for the Catalyst 9600 Switches:

  • Models that support StackWise Virtual:
    • Cisco Catalyst 9606R
  • Asymmetric SUP slot between both the chassis is not supported, so SWV can be configured only on the same supervisor module slot of both the chassis. If on Chassis 1 sup slot module-4 is being used, on chassis 2 only module 4 should be used.
  • Secure SWV is supported only on two-node front-side stacking.
  • FIPS and Secure SWV cannot be configured at the same time because it is a mutually exclusive feature that cannot co-exist. Secure SWV is FIPS 140-2 compliant, and it will encrypt control packets as well. So, enabling FIPS is not required.
  • Only a 128-bit auth key is supported.
  • Secure SWV is not supported on Dual Active Detection Links.

Common Restrictions to configure StackWise Virtual for all the platforms

  • Network Advantage License is required on the switch to recognize StackWise Virtual commands. If a switch is running Network Essential licenses, the commands will not be recognized.
  • Reserved Vlan 4094 from the global VLAN range is used by StackWise Virtual for inter-chassis system control communication between StackWise virtual members. So, before deploying StackWise Virtual in the environment, make sure VLAN 4094 is not used anywhere in the network.
  • Configuration of Dual Active Detection (DAD) Link and StackWise Virtual Link (SVL) must be performed manually. Then for the configuration changes to take effect, the devices must be rebooted.
  • Only Cisco Transceiver Modules are supported.

So, now we have gone through the prerequisites and the restrictions which need to be kept in mind when you are planning to deploy StackWise Virtual in your environment. This understanding will keep you away from most of the challenges during the implementation phase and saves your time in troubleshooting the issues which are caused by the restriction of the respective platform.

StackWise Virtual is one of the multiple technologies which makes your IT environment scalable, flexible, highly available. So, choosing the best technologies and features for your environment to make it scalable, flexible, highly available, reliable, and secure requires expert opinions and we Zindagi Technologies have experts for you who can help you in planning, designing, and implementation of such Campus Network, Data Centers. You can give us a call on +919773973971.

Ankesh Singh
Network Consultant Engineer


Team ZT