Hello,
I test anything such as upgrading on a localhost installation because it is not worth the risk of the downtime caused by an incorrect upgrade. - the hosting provider can get a backup of the site up and running again, but this does take time.
If you have a really busy site, you would get a lot of frustrated users while you are attempting to upgrade a site. - For instance, when I moved from version 3.x to version 4.x it took several days to get the upgrade working correctly.
How to Upgrade DotNetNuke v3.x to v4.4.1Thanks,