Recommended Method for Upgrading C9300 Stack

[qkrrudgh036]

Hi  I’m planning to upgrade a stack of Cisco C9300 switches and would like to ask if there’s a best practice or recommended approach for doing so. The customer has specifically asked whether it’s possible to perform the upgrade without any downtime.

If anyone has experience with this or can share insights on minimizing service disruption during a stack upgrade, I’d really appreciate your input.

Thanks in advance!

[Leo Laohoo]

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@qkrrudgh036 wrote:
The customer has specifically asked whether it’s possible to perform the upgrade without any downtime.

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Not possible in any way, shape or form.  The outage time will depend entire on what is the current firmware and what is the "destination" version.  This is due to a mandatory and automatic micro-code upgrade and the outage time of the micro-code upgrade can vary between 8 to 14 minutes.

Read this:  Cisco 3850: IOS-XE/Firmware Upgrade

[qkrrudgh036]

Given the current situation, could anyone share the most reliable or recommended upgrade procedure?

[Leo Laohoo]

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@qkrrudgh036 wrote:
could anyone share the most reliable or recommended upgrade procedure?

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Posting this again since nobody bothered to read this the first time:  Cisco 3850: IOS-XE/Firmware Upgrade

[Torbjørn · Accepted solution]

You can use "reloadfast"/Extended Fast Software Upgrade (xFSU) to minimise downtime, but as @Leo Laohoo says above - there will have to be some downtime. See the following documentation: https://www.cisco.com/c/en/us/support/docs/switches/catalyst-9300-series-switches/216837-extended-fast-software-upgrade-on-cataly.html