Backing Up to Tape and Creating Duplicates

[SF_Chewy]

Hi,

I've been doing backups to tape (LTO4 specifically) through BE 12.5. I've run into a couple of quirks and I'm wondering if anyone can help. Here is what I am trying to do. I have folders on the server which each consist of about 700 GB to just under 800 GB. I am backing up these folders and then relabling the labels to go with the backed up folder so that it will be easier to identify and retrieve the files when we need them. I want to keep each tape unique to the folder it backs up therefore I do not append to tapes. When I backup the file, I make two copies, an original and a duplicate for offsite. With those stated file sizes I figure that utilizing LTO 4's would just require one tape each folder. Now the issue is when I am backing up the files, they span onto the next blank tape and only write a couple of gigs (like maybe 20 GB) which, in a sense, wastes a tape because I want each tape to be unique to the file. Another issue is that the duplicate spans two tapes, while the first backup only requires one tape. So my questions are how do I ensure that the backup stays on one tape, and how do I ensure that my duplicate stays on one tape as opposed to two when my original backup only required one tape? Also what would be the best practice for this type of job?

Media Set: Keep data indefinitely (no overwrite) and 1 Hr append (which shouldn't matter because my jobs do not append).

I have tried two different policies as follows:
1st policy
- I have a template which backs up the specified folder to tape.
- Overwrites only, because we want each tape to be labeled according to the file it backs up
- Once the first full backup is done, a duplicate begins
- Issue: the issue with this is that the program gets stuck on the duplication, it sits at loading media even though there are plenty of free tapes available. Because of this issue I have stopped using this policy

2nd Policy
- Similar to the first, except instead of running a "Duplicate" job, I just run another full backup with the exact same characteristics as the first job.
- Both are only overwriting and not appending.
- Issue: The backups work fine, however I am getting instances where one backup or the other will require two tapes instead of one like the previous job. When I look at the job statistics, both jobs have the exact same byte count, but one spans two tapes instead of one.

Any help or insight into this would be appreciated

[pkh]

Your 1st policy will not work because you have only one tape drive.  You need two tape drives to duplicate a tape to another tape.  The two tapes need to be loaded simultaneously.

[SF_Chewy]

Ok, thanks for clearing up that first policy mystery for me. An additional point, I do have a Dell TL4000, which I believe has 2 drives and can hold up to 48 tapes. Does duplicating still require me to have another physical device? Or is it or my policy configured wrong?

For the second part, is there any way to control how BE writes to tape in terms of the amount of tapes it requires? To illustrate what I mean (if it was unclear) my first backup of a certain folder takes only one tape, but the second backup requires 2 tapes with the last tape used only using maybe 10 gigs, even though all tapes were blank to begin with.

[Larry_Fine · Accepted solution]

re: For the second part, is there any way to control how BE writes to tape in terms of the amount of tapes it requires?

Basically, no.  Backup Exec will write as much to the tape as the tape drive allows.  When the tape drive signals tat the tape is full, there is nothing more that BE can do.  Your only exception may be to use software or hardware compression (if you are not already and your data is compressable).

[Ken_Putnam]

As Larry says, all you can do to manage how much tape is used, is to turn compression on.  How much you get depends on what data is actually backed up

You can also make subsequemt jobs APPEND using the same media set, and they will start where the first job ended.  You still need to do an OVERWRITE to the media set periodically (weekly for example)

[Larry_Fine]

for the first part (duplicate), your policy looks about right and your 2 drive TL4000 is sufficient.  Do you have any other jobs running at the same time?  Are you getting any alerts?

Maybe one of these will help?
http://seer.entsupport.symantec.com/docs/269808.htm
http://seer.entsupport.symantec.com/docs/347285.htm
http://seer.entsupport.symantec.com/docs/323456.htm

[SF_Chewy]

Thanks for all your help.

Larry: I realized that we have not obtained an LEO licence so that is why we cannot use the second drive we have, which in turn does not allow us to duplicate the tapes. But thank you for the insight you provided.