switch operation during firmware upgrade of cisco SG550 switches in staking mode

[Rondal]

Hi

Due to redundancy I have 3 switches SG550X/GX in hybrid stacking mode.

What exactly happens when a firmware update takes place?

1) Is the firmware update done in sequence so that at any point in time only one switch of the stack is performing the update while the other switches in the stack are still operational? 

2) Or, is operation/traffic of all switches in the stack stopped?

Thanks and best regards 

Roland

PS:

I read this but it does not have an answer to my problem: https://community.cisco.com/t5/small-business-switches/upgrading-cisco-500-series-stackable-switches-in-stacking-mode/td-p/2696972

[balaji.bandi]

In normal Upgrade process, All the Data traffic not interupted, and when the upgreade finishes, Switch expect user intervention to reboot after upgrade.

Any switch upgrade for the SME product required reboot, so upgrade have downtime.

[Rondal]

When I did the firmware update there was no user intervention required to do the reboot. The reboot was done automatically.

So, this means the SMB switches do not support upgrade without downtime of the whole stack.

Do you know of a switch product that allows firmware upgrade of switches in a stack where only one switch of all switches in a stack is down or can even handle firmware updates without downtime?

This would mean that the stack must support different firmware versions in the same stack. This is, according the manual, not possible with the SMB product like the SG550X.

Thanks for your info.

[balaji.bandi · Accepted solution]

Do you know of a switch product that allows firmware upgrade of switches in a stack where only one switch of all switches in a stack is down or can even handle firmware updates without downtime?

Depends on your network. If you like to have Service to be running all the time 24/7

you need to have 2 Stacks in the production environment, and End  device should have capabilities connect to Dual Stack Active/ Active or Active./Stanby mode. so if one stack go down other can take effective.

This is most case in  DC / Server (wheren critical enviroment like health care where you need to have availability all th time) Enviroment. For the End device this solution not really cost effective my point view.

Other Example : Nexus with vPC, Dual Homed device, never seen any down time, since they are dual leg connection

This would mean that the stack must support different firmware versions in the same stack. This is, according the manual, not possible with the SMB product like the SG550X.

yes you are correct. these devices meant to SME/SMB so expected devices connecting to this switches not critical.

make sense ?