Catalyst 3850 SVL - using ISSU to go from 16.9.2 to 16.9.6

[JamesChristley2230]

Hello,

We have a few Cisco Catalyst 3850 12XS switches running IOS-XE 16.9.2 and utilising Stackwise Virtual. We are looking into using the In-Service Software Upgrade (ISSU) feature, but looking at some of the documentation, we are unsure as to whether we are able to go from 16.9.2 to 16.9.6. The diagram at https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst_standalones/b-in-service-software-upgrade-issu.html implies that we can go between any 16.9.x version, but the Release Support Matrix doesn't mention 16.9.6. Additionally, it mentions later on in this page that the 'Software Maintenance Upgrade' package is also required. Is anybody able to clear this up?

Thanks,

James

[balaji.bandi]

9.2 to 9.6 good to go for an upgrade,  if you doing efsu/issu you need to understand some limitations.

read the release notes before upgrade : (some time back i had issue due to some feature so i have to downgrade - need to break SVL )

https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst3850/software/release/16-9/release_notes/ol-16-9-3850.html#task_tmk_gfj_2hb

[Leo Laohoo]

As far as I am aware, ISSU is not supported because you are going from 16.9.X to another 16.9.X.  
It is far better to manually use the Install Mode command: 

request platform software package install switch all file flash:cat3k_caa-universalk9.16.09.06.SPA.bin on-reboot new auto-copy verbose

SMU is a patch file.  It is not a one-size-fits-all.  Make sure to read the Bug ID that is fixed in the SMU before applying the patch.  
NOTE:  In some cases it may say "hitless" but do not take that as gospel.  I have seen some "hitless" SMU that will reboot the entire stack.  

[JamesChristley2230]

UPDATE:

We did this at the beginning of the year and all was good upgrading from 16.9.2 to 16.9.6 with ISSU.

We followed the process outlined at: https://www.cisco.com/c/en/us/support/docs/switches/catalyst-9500-series-switches/214406-in-service-software-upgrade-issu-on-ca.html

We used the 1-step process (haven't tested with the three step).

James