Understanding Acronis Files and Backup logic

Fabio, welcome to these user forums.

The files follow the Acronis backup naming rules as stated in the User Guide.

Backup file naming

A backup file name has the following attributes:

• Backup name.
• Backup method (full, inc, diff: full, incremental, differential).
• Number of backup chain (in the form of b#).
• Number of backup version (in the form of s#).
• Number of volume (in the form of v#).

  For example this attribute changes when you split a backup into several files. Refer to Backup splitting for details.

Thus a backup name may look the following way:

1. my_documents_full_b1_s1_v1.tib
2. my_documents_full_b2_s1_v1.tib
3. my_documents_inc_b2_s2_v1.tib
4. my_documents_inc_b2_s3_v1.tib

If you are creating a new backup, and there is already a file with the same name, the program does not delete the old file, but adds to the new file the "-number" suffix, for example, my_documents_inc_b2_s2_v1-2.tib.

Fabio wrote:

 

1) Is there a limit of increments where it makes sense to do a new full back up?

2) Can I delete manually the older backups (full_b1/inc_b1) to save space?

There is no limit for the number of incremental files but it is not recommended to have a large number because this will put your backup version chain at risk as any problem with a single incremental file in the chain will break the chain at that point, for example, if you have a chain with 30 incrementals and number 15 gets damaged then you would only be able to recover from number 14 backwards all incrementals from 15 to 30 are rendered unusable as each depends on the one before!

It is not recommended to manually delete older backups - it is best to let Acronis do this using the auto cleanup rules.

For example: If you configure auto cleanup to Store no more than 1 version chains then from your file listing above, when your Entire PC (WS2024)_full_b2_s1_v1.tib was created successfully, Acronis would then delete all the previous backup files freeing up over 300GB of space on your drive to allow for the new backup to be stored.

If you do delete any backups manually, then you should run a Validation for the backup task that created those files to reconcile the Acronis Database with the files that remain.

Hi Steve,

thanks a lot for your detailed explanation and the answers to my questions. In the meanwhile I realised that I can control the cleaning policy (https://forum.acronis.com/forum/124082). So, it makes sense to find an optimum between full backup (time consuming) and number of increments (risk of damaged files). Also I have to find the optimal number of stored version chains (conflicting with space). I decided to have 3 version chains and 5 increments.

Thank you again for your help. I have only one curious question. Why was the first chain not removed with this setting:

Delete version chain older than 7 days (default setting)

Shouldn't the first version chain:

Entire PC (WS2024)_full_b1_s1_v1.tib
Entire PC (WS2024)_inc_b1_s2_v1.tib
.......
Entire PC (WS2024)_inc_b1_s6_v1.tib

be deleted with this setting since the chain is older than 7 days?

Fabio

Fabio, there seems to be an issue with the option to delete version chains older than 7 days, as other users have reported the same issue.

The age of the version chain is only counted after the final file for the chain has been created, so for your first chain, this would be: 02.08.2016  09:08       3'726'209'024 Entire PC (WS2024)_inc_b1_s6_v1.tib

So, 7 days should have been on 09.08.2016 but given your post shows new files being created later than this date, it looks like this auto cleanup rule has not been actioned.

My preference is to use Store no more than X recent version chains which does work well for me.

Hi Steve,

Thanks for this information. I just wanted to know if I understand the cleaning rules. It is also my preference to keep the last X version chains. I hope this works.

Fabio

Hi Steve

The Acronis user GUI has the following cited in the "help" menu for "Auto Cleanup". 

   Delete versions older than [defined period] (full method only) 

   Delete version chains older than [defined period] (incremental and differential only)

   Store no more than [n] recent versions (full method only) 

   Store no more than [n] recent version chains (incremental and differential only)

   Keep size of the backup no more than [defined size] 

However I cannot find anything relating to Auto Cleanup in the user options where I would expect it. Is it in the Tools menu as "System Cleanup? If so, I am fearful I will clean my system of all data. I regret I am a bit of a stickler for verbatim matches. Acronis Drive Cleanser looks similar, and I figure it wipes drives, so that should be OUTLINED IN RED to tell users what this this tool will do. I apologize in advance if the blog already addressed any of this.

Thanks!

Brian

Also  users need a more complete notion of what the system is doing at the moment, such as messages saying "current operations will fail", and why a backup job is "queued".

Brian, automatic cleanup only applies to ATI Backup tasks.  These rules are set on a task by task basis (on the Backup Scheme page of the task) and the only files that are cleaned (removed / deleted) are those related to the task where they apply.

Other Acronis tools have different purposes that would depend on each tool, these are separate from the purpose of Acronis True Image.