Backups

The Virtual Server Agent (VSA) proxy on a Google Cloud Platform service account can perform crash consistent backups for all instances.

You can perform full, incremental, or synthetic full backups of instances. The first backup of an instance is always a full backup, regardless of the selected backup type.

What Gets Backed Up

The following data is backed up by the Virtual Server Agent:

• Instances (powered on or powered off)

• Configuration files for each instance

• Instance disks

What Does Not Get Backed Up

The following data is not backed up by the Virtual Server Agent:

• Images

• Instances that are encrypted with a customer-managed encryption key or a customer-supplied encryption key

• Local solid-state drive (SSD) scratch disks

  When local solid-state drive (SSD) scratch disks reside on an instance with other supported disks, during the backup operation, the SSD scratch disks are skipped. The other disks are included in the backup.

• Regional persistent disks (standard and SSD)

  When regional persistent disks (standard and SSD) reside on an instance (either with or without other supported disks), the backup job will fail.

Backup Types

You can perform the following types of backups, either immediately or on a schedule.

• Full backups: Back up the entire instance. This is the most comprehensive backup.

• Incremental backups: Back up instance data that has changed since the most recent backup.

• Synthetic Full backups: Consolidate instance data from the most recent full backup with subsequent incremental backups.

Backup Process

A backup operation for Google Cloud includes the following stages:

1. Create a snapshot of all disks associated with the instance.

2. Create disks from snapshots.

3. Attach the created disks to the proxy.

4. Populate the config file and save it.

5. Read each attached disk and back up disk data.

6. Delete the snapshots and disks created as part of the backup process.