Backup storage in a public cloud

General requirements are listed in General requirements.

Note the additional requirements for backup storage with the public cloud destination:

  • When working with public clouds, Backup Gateway uses the local storage as the staging area as well as to keep service information. It means that the data to be uploaded to a public cloud is first stored locally and only then sent to the destination. For this reason, it is vital that the local storage is persistent and redundant so the data does not get lost. There are multiple ways to ensure the persistence and redundancy of local storage. You can deploy Backup Gateway on multiple cluster nodes and select a good redundancy mode. If Virtuozzo Hybrid Infrastructure with the gateway is deployed on a single physical node, you can make the local storage redundant by replicating it among local disks. If Virtuozzo Hybrid Infrastructure with the gateway is deployed in a virtual machine, make sure it is made redundant by the virtualization solution it runs on.
  • Make sure the local storage cluster has plenty of logical space for staging. For example, if you perform backup daily, provide enough space for at least 1.5 days’ worth of backups. If the daily backup total is 2 TB, provide at least 3 TB of logical space. The required raw storage will vary depending on the encoding mode: 9 TB (3 TB per node) in the 1+2 mode, 5 TB (1 TB per node) in the 3+2 mode, etc.
  • A separate object container is required for each backup storage cluster.

To better understand how to calculate the hardware configuration for backup storage with the public cloud destination, consider the following example with RAM and CPU reservations.

If you have 1 virtual machine (1 system+metadata disk and 1 storage disk) and want to use the 1+0 encoding mode with the disk failure domain, refer to the table below for the calculations. Note that in this configuration redundancy is provided by the virtualization solution.

Backup storage in a public cloud
Service The only node
System 4.5 GB, 3.3 cores
Storage services

1 storage disk1 and 1 metadata on system disk (each takes 0.5 GB and 0.2 cores), that is 1 GB and 0.4 cores in total

Backup Gateway 1 GB, 0.5 cores
Service reservations 6.5 GB of RAM and 4.2 cores
Minimum hardware configuration 8 GB of RAM and 4 cores
Recommended hardware configuration 16 GB2 of RAM and 6 cores