111 Copyright © Acronis International GmbH, 2002-2013.
18 Glossary
A
Agent (Acronis vmProtect 9 Agent)
An application that performs backup and recovery of the virtual machines and enables other
management operations on the VMware ESX(i) infrastructure such as task management and
operations with available backups, machines, etc.
Acronis vmProtect 9 includes the Agent for backing up virtual machines residing on a VMware ESX(i)
virtualization server which the Agent is connected to. There could be several ESX(i) hosts or a vCenter
managed by one Agent. The best practice is to register vCenter on the Agent instead of specific ESX(i)
hosts which are managed by this vCenter. Otherwise, vMotion (p. 121) will not be supported.
The Agent component can be either Windows-based, i.e. installed on a Windows platform, or
Appliance-based, i.e. running on a special virtual machine on an ESX(i) host.
Always Incremental archive
A new generation of the archive (p. 111) format which may contain several backups (p. 111) from
different virtual machines inside. All backups are saved to this archive in incremental mode (p. 118).
Physically all data is located inside one file as opposed to Legacy mode archive format where each
backup is stored in a separate TIB file. Here is the description of how the backups rotation is
performed inside the Always Incremental archive:
When one backup becomes expired according to the pre-defined retention rules (which say for
example to “delete all backups older than 5 days”), the program marks the old blocks which belong
to the expired backup as “free” ones. The blocks of the expired backup which have any dependencies
(they may be used in newer backups due to incremental backup technology) are not marked as
“free” to ensure the archive consistency. The archive will still be taking the same space on the
storage as before. However, newer backups saved into this archive will first write data to the “free”
blocks and will increase the total size of the archive only when all the “free” blocks are used.
This approach allows us to keep the archive size as small as possible and prevents it from growing
indefinitely.
Archive
See Backup archive (p. 112).
