How to migrate SharePoint 2010 to SharePoint 2016 On-premise?

Question

We have current environment set up with SharePoint 2010 on-premise and we want to migrate to SharePoint 2016 on-premise.

My question is, is it required to upgrade my custom solution to 2013 first and then upgrade to 2016? Will my custom solution created for 2010 work with out any modification in new environment SharePoint 2016 on-premise?

Also we have custom forms in infopath. I found this link which says SharePoint 2016 will support infopath forms of 2013. same question for it too. Is it required to upgrade my custom solution to 2013 first and then migrate them to SharePoint 2016? Or they can be migrate directly?

Thanks in advance.

Answer 1

Although not a direct duplicate, I hope you have come across this similar question of 2010 to 2016 upgrade: Migrate from SharePoint 2010 to SharePoint 2016 directly?. Additionally, the 2010 InfoPath in 2016 SharePoint has been previously asked here, but not answered: Sharepoint 2016 and infopath 2010. There's an alternative community question about the subject elsewhere, which doesn't answer the question either.

In a nutshell, you need to update your environment to 2013 first, and have the 2013 visual look thoroughly applied in your site collections.

Custom solutions may or may not work without an upgrade to 2013, but I'd pretty safely bid for a no-go. For InfoPath, I actually have a gut feeling that 2010 versions could work in 2016, as 2010 version is very similar to 2013 version. This is all speculation, so again based on the general recommendation, you should update the forms to 2013 as well. However, do note that at least for one person the functionality of 2010 forms was lost when Office tools were adapted to 2016 version. Whatever you plan to do, you should do it in a test environment at first anyway.

Answer 2

The correct answer to both questions is "it depends". I have successfully upgraded many farms and written PowerShell scripts to crawl my farms looking for InfoPath forms in Form Libraries as well as List Edit and New item forms. We use the resulting list of forms to first, check to see if they are still in use, then later, for testing. Probably the biggest issue is when you migrate from Classic to Claims Authentication. This may break your InfoPath forms if your are getting the current user and then passing it outside the form.

We also script the discovery of every custom assembly and custom field control. Then, again, we evaluate if the customization is still necessary and if so, test it in the upgraded farm. 2010 customizations did not use a versioned Layouts folder. In 2013 and 2016 we use a 14 & 15 folder respectively. So, it is POSSIBLE that the only change you will need to make is in the deployment path of your Solution. (Otherwise you will get a file not found error.)

If you are using parts of the API that have been deprecated, then you will have to rewrite the code. This you can test by recompiling against the 2016 SharePoint DLLs.

There is a lot of other discovery you will have to do, as Moe indicates above, before you can move from 2013 to 2016, you have to ensure that you have no sites in 2010 mode. We just write scripts to perform this entire audit in 2010, then script the same in 2013, then upgrade to 2016 and test again.

<SelfPromotion> There is a great class on all this on Pluralsight. Upgrading Your Farm to SharePoint 2016 </SelfPromotion>