Cisco C9407 stackwise virtual IOS upgrade

[Adnan Khan]

Cisco C9407 StackWise virtual current ios is16.9.4 and target is 17.3.3. Can the switches upgrade one by one or ISSU? with 0 downtimes?

[Leo Laohoo]

If it is possible, hold off the upgrade to 17.3.3 because 17.3.4 will be released on July 2021.  

0 downtime is impossible because there will be a micro-code upgrade. 

[Mohsin Alam]

Zero downtime not possible.

best place for everything you want to know:

https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst9400/software/release/17-3/release_notes/ol-17-3-9400.html

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