cancel
Showing results for 
Search instead for 
Did you mean: 

Backup Exec Compression Settings Questions

jerrys79
Level 4

Hi, i'm trying to figure out the best method when compressing data using Backup Exec.  I currently backup my servers to disk using remote agents and then I run a duplicate job to tape (LTO5).  I am running BE 2014 and the data is a mix of everything from file servers to sql, ad and exchange databases to hyper-v vm's.  My questions are:

-Should I run software compression when doing the initial backup to disk and then no compression on the duplicate to tape? 

-Should I run no compression for the inital backup and then hardware compression to tape?  This is how i'm currently doing things but disk space is slowly becoming a concern and i'm starting to question why it was ever set up this way.

I found that compressing both times is not a good idea according to: "Data that has already been compressed or random data (such as encrypted data or MPEG files) may actually expand by about five percent when attempting to compress it further. This can reduce drive throughput." http://www.symantec.com/business/support/index?page=content&id=TECH49521) 

I did read somewhere that the compression ratio between hardware and software compression are almost equal. 

I also read that the only disadvantage to software compression is: "Depending on your environment some system overhead might be involved. However, it’s quite negligible." http://www.symantec.com/connect/articles/understanding-compression-backup-exec.  pkh asked in that thread on April 12, 2014: "If this is true, why would one want to use hardware compression?" It was never answered and i'm hoping to find an answer or at least find what is considered a best practice.  The only answer I can think of is if you backup direct to tape. 

One last note, encryption is not involved.  I understand "if you require both encryption and compression, then both have to be software to achieve any compression.  The data is compressed and then encrypted on the server" according to: https://www-secure.symantec.com/connect/articles/compression-short-explanation.

 

Thanks in advance.

1 ACCEPTED SOLUTION

Accepted Solutions

pkh
Moderator
Moderator
   VIP    Certified
The compression ratio for hardware and software compression is roughly the same. If you do not need to save disk space then no compression to disk and hardware compression to tape

View solution in original post

3 REPLIES 3

pkh
Moderator
Moderator
   VIP    Certified

If you are running out of disk space and need compression, then you should do software compression to disk and then no compression when duplicating to tape.

However, note that the impact of software compression is NOT negligible.  It is noticable, but not a killer.

jerrys79
Level 4

Thanks pkh.  I will switch to software compression for now.  From your experience, do you know if it has about the same compression as hardware?  I don't want to take care of my disk space issue and then end up with a problem of having a large amount of tapes if the compression isn't as good.  I will monitor my environment and compare before and after settings.

Also, if disk space wasn't an issue, what would you recommend as a best practice?

Thanks for your help.

pkh
Moderator
Moderator
   VIP    Certified
The compression ratio for hardware and software compression is roughly the same. If you do not need to save disk space then no compression to disk and hardware compression to tape