While Zerto ZVM can work from an external database and can run if that database is placed in an availability group (always on setup), our upgrade process at the moment doesn't support it. 

An administrator may set up Zerto to work with external SQL database that's configured to be always on. When the time comes to upgrade Zerto to a newer version, the upgrade process might fail due to several reasons, for example, locks in the database.


Please follow these steps before starting the upgrade process:

1) Before install/upgrade change the connection string back to SQL Server 

2) Delete/Remove AlwaysOn 

3) Install/upgrade 

4) Define AlwaysOn 

5) Change connection string.