BackupExec 2010 differential and full backup same dimension

[PrismaInf]

I' ve this configuration:

Backup exec 2010 r2 on windows 2008 std r2, i run a daily job for differentials backup and on saturday run a full backup job. The destination of this job are a Nas with two directory, one for differentials and one for full... The problemi is that differentials backup have the same dimension of full backup. My nas  now is full. Do you have any advice to avoid thi problem??

[CraigV]

Hi,

I'd start by checking your retention settings on your media sets. If they are set to retain data for too long, there is a good chance you're simply filling up the NAS instead of overwriting the files correctly.

Thanks!

[itsmeaffinity]

Hi

Dimension is you are talking about size in this case. Differential backup basically backup each file which is changed after full & incremental due to which it it consumes more disk space .bt while doing restore the you only require last full & last differential.

In compare to that if you to do incremental backup then if will only backup the changes after full & will reset the archive bit which differential will not do so backup doesn't consume that disk space as full or differential but while doing restore you need to have last full & all incremental after that to do restore

So in your case if size is concern you can change your backup method to incremental & full or you can change the overwrite protection period for the full & differential backup that means if you are doing full on saturday & differential daily then next week you can overwrite the last wek differential by keeping overwrite portection to 7 days & append infifnite

Hope this help & if it is so you can mark this solved

Thank You

[PrismaInf]

My retention policy is 6 days for overwrite, but the problem is that full backup is 500 Gb and differential is 500 Gb so is impossible that all file are changed... maybe full and differentials need to be saved in the same directory??

[itsmeaffinity]

Hi

Same directory would not make such difference but can you confirm if the file are getting overwritten or not

& how many server you are backing & all or windows server & and all flat file backup or some application bacup too like sql ,exchange

Or may be you can try taking incremental & full see if that help

Thank You

[PrismaInf]

i confirm the file are owerwritten i try to backup 4 server one of those has Lotus domino

[CraigV]

...create another policy for differential backups and see if you get the same issue...

[PrismaInf]

for policy you intedna nother job or another selection ??

[itsmeaffinity]

Hi

Make new policy with two new template & add new selection & try  doing small backup if that works & then add other server too

Thank You

[CraigV]

I'd go with the same selection list at first. If it still happens with a new policy and the same selection list, then you need to eliminate the original selection list by creating a new one...

[pkh]

@prismainf - On the Devices tab, right-click on your B2D folder and check that you have not checked the allocate maximum size property (see below).  If you had, then each new .bkf will be created with the maximum size regardless of how much it is used.

[sbora]

What is the backup method used - Archive bit or Modified time?

Incremental or Differential-Using Modified time,jobs backup same amount of data as Full backup if the same selection list as in the Full job is not used.

http://www.symantec.com/business/support/index?page=content&id=TECH90495

[Colin_Weaver]

On a similar note - if using Modified Time check that something like your antivirus package is not changing the times (we had a report from another customer where the AV package, that was not ours, caused the problem)

[Ken_Putnam]

Make sure that you are using the same selection list for both the FULL and DIFF jobs

[server_guy]

What a painful read this thread is!!! If youy don't know what you're talking about, stay out of the discussion. This is an issue of the SIZE of the differential backup. NOT selection lists, NOT incremental VS differential, NOT media retention time... cripes people!

I have the same problem and I'm backing up to tape. My diff's are equal in size to the weekend fulls as well. I'm wondering what impact 'Diiferential - Using modification time' vs 'Differential - Using archive bit' has. I beleive this may be part of the problem. I'm using the first choice listed above. I will try changing it and see what comes out of it.

[CraigV]

...not sure who it was directed at, but unfortunately some of the threads are "painful"...the joys of not being on the other side of a phone/Webex session and checking during work breaks =/

Anyways, this is how general troubleshooting goes, so everything mentioned was tried/debunked etc. etc...

[ZeRoC00L]

Check the properties of your FULL backup and check if the reset archive bit option is selected: