A whole VM snapshot for example that is reliant on VSS could incur an unacceptable long IO stun duration when it occurs.

You should consider complimentary backup solutions that backup/snapshot the entire server (or VM) for SQL Server, but sometimes these technologies are limited or have too much of an impact on the server. Not hardware failure but ransomware (crypto-locking file) attacks have been the cause. Recently, by far the most frequent and common disaster recovery scenario for my clients has been the need for a complete, bare-metal rebuild or restore of the master database. You can use the BACKUP MASTER KEY statement to create those backups.Not many disaster recovery or SQL migration/upgrade scenarios require the SQL Server instance service master key to be restored. It is therefore important that you have a good backup of each DMK. It potentially can be required to access all your encrypted data. The Database Master Key is the root of the database encryption hierarchy in SQL Server. And remember to also safe that passphrase, as without it you cannot restore the key. The backup itself should be stored in a secure off-site location. This should, as always when dealing with encryption keys, be a strong and unique passphrase. The second is the password that is used to protect the backup file from prying eyes. This file must not exist, as an existing backup file will cause an error. The first is part of the TO FILE clause and specifies where the backup will be stored. Like the BACKUP SERVICE MASTER KEY statement, the BACKUP MASTER KEY statement has just two 'parameters'. Note that the word 'database' is omitted from this statement to prevent confusion with the BACKUP DATABASE statement.

Backup master key sql server