ONTAP Downgrade procedure

[Quang-Chinh]

Hello all, 

A customer asked is scheduling ONTAP upgrade from 9.3 to 9.7.

He generated the associated upgrade advisor and has some question regarding some of the steps.

It's mentionned that they need first to downgrade from 9.7Px to 9.6P9 before 9.3P17 (page 9 of the enclosed documents). 

The step is not clearly described into the documentation. 

How do we do this step? 

Do we need to install the 9.6P9 version, change the images and system node revert-to -node nodename -version 9.6P9 ?

During the upgrade, ONTAP will be upgraded to 9.5P17 first and then to 9.7Px

Why are we not doing the revert to 9.5P17?

Thank you so much for help on this.

[akiendl]

Hi Quang-Chinh,

I assume you mean the backout plan? This is only used if you hit a severe issue and would need to downgrade to the old release.

Usually if you hit any issue it is advised to contact NetApp support to evaluate the situation of the issue (which is very, very rare) and come up with a plan forward.

The upgrade itself does not contain any downgrade steps. so you basically update from 9.3P17 to 9.5Px (usually the latest p-release) to 9.7Px.

Hope that answers your question,

ak.

[SpindleNinja]

That's the backout plan should you need to revert to 9.3.  Since this is a double upgrade downgrade has slightly different steps.  Check out the matrix on this doc, page 9/10.   

see here: https://docs.netapp.com/ontap-9/topic/com.netapp.doc.dot-cm-ug-rdg/Upgrade%20revert%20or%20downgrade.pdf 

Note that during the 9.3 to 9.7 upgrade it's actually upgraded twice in the background first to 9.5 then to 9.7.     Be sure to check with the IMT that everything is supported along the way too. 

I agree with the other person in this thread that troubleshooting forward is the preferred method before reverting. 

[Quang-Chinh]

Thanks for your answer.

Sure, the recommandation will be to contact TSC first/before the downgrade itself to get assistance and ensure the downgrade is the last solution.

Based on the documentation, if I'm understanding properly:

You can downgrade from... To...
ONTAP 9.1 ONTAP 9
Note: Downgrade of a two-node MetroCluster
configuration from ONTAP 9.1 to 9 is disruptive.
You must perform a revert from... To...
ONTAP 9.8 ONTAP 9.7
ONTAP 9.7 ONTAP 9.6
ONTAP 9.6 ONTAP 9.5
ONTAP 9.5 ONTAP 9.4
ONTAP 9.4 ONTAP 9.3
ONTAP 9.3 ONTAP 9.2
ONTAP 9.2 ONTAP 9.1
ONTAP 9.1 or ONTAP 9 Data ONTAP 8.3.x

So, that means we can only downgrade feature version by feature version. upgrade can be done 2 by 2 but not the downgrade?

At the end, customer wants to clarify and have something to present to the board in case of revert is needed.

And also, in other terms, that means the information in the upgrade plan are "inacurate" regarding versions?

Thanks again.

[SpindleNinja]

Yes, Upgrade you can double hop.   9.1 -> 9.3 -> 9.5 -> 9.7 

Downgrade is typically more granular and is disruptive and a very last resort typically done at the direction of Support.   

You mean this line?  "Note:Please note that direct revert from ONTAP 9.7P8 to ONTAP 9.3P17 is not allowed. You must perform a revert from 9.7P8 to9.6P9".        I think it's just saying you can't go directly,  i've not ever seen a UA spell out every step in a downgrade.    Or, (speculation here) there is something specific to that model of controller where system firmware hadn't changed between 9.3 and 9.6. highly unlikely though.     

Support is typically engaged before doing so.  I think i've only reverted a cluster 1 time in the last 6+ years.   And i've not ever done the "direct" 9.3 to 9.7 upgrade because customers always wanted to verify between major versions. 

[paul_stejskal]

That line merely reads "latest 9.6 P release" is what you will need to revert to for going back to 9.3. Everyone is correct, it's in case of the upgrade causing issues.