Forum Discussion

CVWO's avatar
CVWO
Level 2
13 years ago

Least Network Traffic Solution

Hello everyone,

I have a quick question:

We are planning to set up a new backup system using BackupExec 2010. The plan includes a daily full offsite HDD backup from house A that will run over a wireless link (approx. 100Mbit throughput) to house B. This should be using the deduplication option to minimize network traffic. However, we would prefer to run the deduplication on a dedicated backup server in House A. This server in House A should keep its own copy of the data. Running the deduplication on the clients is not an option we would like to explore.

The offsite Backup should be an exact duplicate of the Data in house A. The resulting Data from the deduplication in house A should simply be mirrored to house B. It is, however, crucial that the Backup in house B is completely independent from house A, and that recoveries can be made even if the main backup server in house A would be completely destroyed or similar.

The question is, does the deduplication option allow this behaviour? Could we simply use a SMB share instead of a server in house B to mirror the changes? If this option is not reasonnable, what other option is there that minimizes network traffic over the wireless link?

I asked our IT professional, but he was unsure if the mirrored backup would be independant. Unfortunately, we need to know this before we start the project.

Thanks in advance!

  • Yes. What you are trying to do is possible.  It is called optimised dedup.  You have to have a media server in each location with the dedup option.  You do a backup locally and then use a duplicate job to duplicate the dedup-ed data over to the remote site.  Only the changed data blocks will be transmitted over the WAN link.  You can read about this feature in the Admin Guide.

  • Yes. What you are trying to do is possible.  It is called optimised dedup.  You have to have a media server in each location with the dedup option.  You do a backup locally and then use a duplicate job to duplicate the dedup-ed data over to the remote site.  Only the changed data blocks will be transmitted over the WAN link.  You can read about this feature in the Admin Guide.

  • Thanks a lot for the helpful answers. We will probably go that way.

     

    Some follow-up questions though:

    Short version:

    Can i use GRT with the dedup'd data that remains on CASO as long as CASO is available?

    And, if CASO is destroyed, is BE able to recover the catalogs from opt-dedup (Can i, after setting up a new CASO, do a complete restore of the opt-dedup'd Data, even if i do not have any CASO catalogs whatsoever)?

    And, can i use GRT when i write back the opt-dedup'd data to the CASO dedup folder (or a regular disk folder)?

     

    Long version:

    The Admin guide says "Note: Optimized duplication is not available for backup sets that are enabled for Granular Recovery Technology."

    Concerning that, i found this:

    http://www.symantec.com/connect/forums/optimized-deduplication-and-grt

    Which links to http://webobjects.cdw.com/webobjects/media/pdf/symantec/Backup-Exec-2010-Deduplication-Options.pdf.

    ("Backup Exec’s Granular Recovery Technology (GRT) can also be used in conjunction with Optimized Duplication.")

    It seems to me this was not answered sufficiently (at least there was no confirmation for what the last poster said). So the question remains for me:

    Does that mean in case i need to use the opt-dedup data, i first have to write it back to free disk space on the CASO (What exactly is meant by stage to disk in the second link (english is not my first language)?)? Can i do this:

    BU to dedup (with GRT on CASO) to opt-dedup (without GRT on Server2)?

    Or, if not, what about:

    BU to disk (with GRT on CASO) to dedup (without GRT on CASO) to opt-dedup (without GRT on Server 2)?

    And what if CASO will be completely unavailable? Will Server 2 be enough to do a full recovery? The reason i ask this is because it seems there is no way to keep the opt-dedup catalog on the same server as the opt-dedup folder (on Server 2). However, the scenario must support a full recovery, even if the CASO is completely destroyed. Can BE rebuild the catalog from the Server 2 data?

    This seems to be indicated when it says "You must inventory and catalog the media on the destination server before you recover any files from the duplicated backup set. You must do this regardless of how the catalog sharing option is configured for CASO." (http://www.symantec.com/business/support/index?page=content&id=HOWTO23342). (Or does this apply to OpenStorage only?)

     

    Thanks so much in advance.