Video Screencast Help

how much file size for example 100 GB

Created: 20 Sep 2011 • Updated: 11 Oct 2011 | 5 comments
This issue has been solved. See solution.

Hi,

running Backup Exec for Windows Server 12.5.
If I am going to backup 100 GB files to a back-to-disk folder,
what total size will the backup medium(s) have ?
(much more than 100 GB?)

Kind regards,
Roland

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CraigV's picture

Hi Roland,

 

For a once-off backup it will be 100GB at a maximum. You might get some compression, but I am not sure how much exactly, if at all.

If you want to run multiple jobs, you'd need X-number of jobs to keep x 100GB. Say you want to keep 6 iterations of the backup, you'd need 600GB at a minimum, but build in overhead with data growth.

 

Thanks!

Alternative ways to access Backup Exec Technical Support:

https://www-secure.symantec.com/connect/blogs/alte...

Roland Schmid's picture

Hi Craig,

thank for answering.

For a once-off backup it will be 100GB at a maximum. You might get some compression, but I am not sure how much exactly, if at all.

If you want to run multiple jobs, you'd need X-number of jobs to keep x 100GB. Say you want to keep 6 iterations of the backup, you'd need 600GB at a minimum, but build in overhead with data growth.

 

this means if I run once a full backup of 100 GB and and afterwards differential or incremental scheduled backups the 100 GB will grow as the amount of new or changed files grows ?

Kind regards,
Roland

 

CraigV's picture

Hi Roland,

 

Quite correct...so you'd have the following scenario per day:

Sunday (FULL) - 100GB

Monday (INCR/DIFF) - 1GB changed; 1GB backed up

Tuesday (INCR/DIFF) - 19GB changed; 10GB backed up

etc for the remaining run of your DIFF/INCR backup. Once you get to Sunday again, it would back up your data FULL...so you might be backing up 120GB the next week; 120GB the week thereafter; 105GB the week after that etc.

It depends on the change in your data which is a bit difficult to predict.

 

Thanks!

Alternative ways to access Backup Exec Technical Support:

https://www-secure.symantec.com/connect/blogs/alte...

pkh's picture

Differential backup will backup all the files since the last full backup.  In Craig's example above, the Tuesday differential backup will backup all the files changed since Sunday, so it will backup 11GB, 1GB from Mon and 10GB from Tue.

I would STRONGLY suggest that you familiarise yourself with the Preparing for Backup section of the Admin Guide.

SOLUTION
Roland Schmid's picture

I would STRONGLY suggest that you familiarise yourself with the Preparing for Backup section of the Admin Guide.

thank you, yes I am about to study it.
nevertheless I like to ask to dispel doubts

Kind regards,
Roland