Acronis Backup & Recovery 10 Advanced Workstation TIDLBPDES5 Manual De Usuario
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TIDLBPDES5
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When backing up in the full backup mode similar data from different sources. Such is the case
when you back up operating systems and applications deployed from a single source over the
network.
If you back up, say, 100 similar systems to a deduplicating vault, the archives in total will occupy
less space as compared to backup to a normal vault. Best practice is to back up one of the similar
systems first, so that Acronis Backup & Recovery 10 Storage Node registers all the system's files
as potential deduplication items. This will lead to faster backup processes and less network traffic
(because of effective deduplication at source), regardless whether the backups are performed
simultaneously or not.
when you back up operating systems and applications deployed from a single source over the
network.
If you back up, say, 100 similar systems to a deduplicating vault, the archives in total will occupy
less space as compared to backup to a normal vault. Best practice is to back up one of the similar
systems first, so that Acronis Backup & Recovery 10 Storage Node registers all the system's files
as potential deduplication items. This will lead to faster backup processes and less network traffic
(because of effective deduplication at source), regardless whether the backups are performed
simultaneously or not.
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When performing incremental backups of similar data from different sources, provided that the
changes to the data are also similar. Such is the case when you deploy updates to these systems
and apply the incremental backup. Again, it is recommended that you first back up one machine
and then the others, all at once or one by one.
changes to the data are also similar. Such is the case when you deploy updates to these systems
and apply the incremental backup. Again, it is recommended that you first back up one machine
and then the others, all at once or one by one.
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When performing incremental backups of data that does not change itself, but changes its
location. Such is the case when multiple pieces of data circulate over the network or within one
system. Each time a piece of data moves, it is included in the incremental backup which becomes
sizeable while it does not contain new data. Deduplication helps to solve the problem: each time
an item appears in a new place, a reference to the item is saved instead of the item itself.
location. Such is the case when multiple pieces of data circulate over the network or within one
system. Each time a piece of data moves, it is included in the incremental backup which becomes
sizeable while it does not contain new data. Deduplication helps to solve the problem: each time
an item appears in a new place, a reference to the item is saved instead of the item itself.
Deduplication and incremental backups
In case of random changes to the data, de-duplication at incremental backup will not produce much
effect because:
effect because:
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The deduplicated items that have not changed are not included in the incremental backup.
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The deduplicated items that have changed are not identical anymore and therefore will not be
deduplicated.
deduplicated.
2.11.6.3. Deduplication ratio
The deduplication ratio shows the size of archives in a deduplicating vault in relation to the size they
would occupy in a non-deduplicating vault. The higher the deduplication ratio, the more
advantageous the deduplication.
would occupy in a non-deduplicating vault. The higher the deduplication ratio, the more
advantageous the deduplication.
For example, suppose that you are backing up two files with identical content from two machines. If
the size of each file is one gigabyte, then the size of the backups in a non-deduplicating vault will be
approximately 2 GB, but this size will be just about 1 GB in a deduplicating vault. This gives a
deduplication ratio of 2:1.
the size of each file is one gigabyte, then the size of the backups in a non-deduplicating vault will be
approximately 2 GB, but this size will be just about 1 GB in a deduplicating vault. This gives a
deduplication ratio of 2:1.
Conversely, if the two files had different content, the backup sizes in non-deduplicating and
duplicating vaults would be the same (2 GB), and the deduplication ratio would be 1:1.
duplicating vaults would be the same (2 GB), and the deduplication ratio would be 1:1.
What ratio to expect
Although, in some situations, the deduplication ratio may be very high (in the previous example,
increasing the number of machines would lead to ratios of 3:1, 4:1, etc.), a reasonable expectation for
a typical environment is a ratio between 1.2:1 and 1.6:1.
increasing the number of machines would lead to ratios of 3:1, 4:1, etc.), a reasonable expectation for
a typical environment is a ratio between 1.2:1 and 1.6:1.
As a more realistic example, suppose that you are performing a file-level or disk-level backup of two
machines with similar disks. On each machine, the files common to all the machines occupy 50% of
machines with similar disks. On each machine, the files common to all the machines occupy 50% of
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