An error is reported when workers cannot reach SQL Servers. There can be different causes of such errors, for example:
As the backup process is based on the BACPAC export, workers must connect using any SQL account to access the database.
The virtual network where all Veeam Backup for Azure workers are running must be enabled in the SQL server firewall.
In case of the SQL Managed Instances, enable the public endpoint in the instance networking options and then configure the security group of the network where the SQL Managed Instance is connected.
If there are any other firewalls between Veeam Backup for Azure and the SQL Servers or SQL Managed Instances, they must be configured as well.
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