'Backup to Disk' backups to tape

[TerryPrior]

I'm looking to change my backup method shortly. Instead of doing nightly full backups to DLT (I currently have 5 separate DLT drives, not 'pooled'), I am going to be using 'backup to disk' on my NAS device.
The basic plan is:
Nightly, do a 'differential' backup, to disk (I don't anticipate more than a few hundred MB per night).
Also, once a month, do a full month-end backup (total approx. 250GB) to disk. Once this backup is complete, I want to utilise my current DLT drives and backup the full disk backup to tape for off-site storage.

I will be using my NAS device for the 'backup to disk' folders.

My main questions are:
Should I create one huge backup job, to back up all (30) of my servers, or break it down into smaller jobs?

Once my full monthly backup is done, and assuming I elect to have one big job, I understand it is saved as one big .bkf file. Would it be possible to backup this one big file (250GB) to my 5 DLT drives? If so, how?

Your help is appreciated.

Rgds

Terry

 

[SQLBill]

What do you mean by "backup this one big file (250GB) to my 5 DLT drives"? Do you mean 'back up the file to tape' or do you really intend to put part on each of the 5 drives?

I backup a SQL Server 2000 database that's 190+GB. I first back it up to disk (a .bak file), then I use BE 8.6 to copy that file to tape. The only issue you will have is ensuring that you start your tape backup AFTER the backup to disk has FINISHED.

-SQLBill

 

[Rols]

By the way you will not be able to use all 5 tapes drives to back up the big (250mb) file. Backup Exec does not support multiplexing.

Also if you need to do a restore from tape you will first have to restore the big (250mb) backup file to disk and then restore the files. Hence i would not recommend this solution.

If you must backup to disk I would do a full backup to disk each week and differential backups to disk each weekend and then do a full backup to TAPE each month.

Is there a reason why you dont like backing up directly to tape?

Cheers

Rols

 

[TerryPrior]

Thanks for the advice guys. I am required to have monthly backups on tape and stored off-site (for legal reasons). The reason I'm keen to use disk backups as much as possible is that my NAS device is situated at our disaster recovery site, so in the event of a disaster and we have to leave our main building and go there, the backups will be available immediately.
I was wondering if there was any way to use all 5 of my DLTs in an 'array' or 'pool' so that I can spread the whole backup across multiple tapes, and not have to worry about changing tapes. I get the feeling from what you've said that this is not going to be possible....

Cheers

Terry

 

[SQLBill]

I do just about what you are trying to do. I back up my SQL Server databases to disk, then copy those files to tape using BE 8.6. However, I have an autoloader and set up media pools for each of my backup jobs. I can't tell the job to spread across multiple tapes, it just starts on one tape and continues onto another as needed.

-SQLBill

 

[Qdog]

I would break the job up into seperate jobs per server. That way if the .bkf file goes south on the NAS device (they do and it will and chksk will not bring it back) you will at least have the possibility of having other .bkf files that may work.

You can use your tape drives in a cascaded drive pool so that when the first drive's tape fills, the backup will span to the next drive in the pool and so on, etc. The tape drives all have to be the same make and model and preferably the same firmware.

With Backup Exec 9.0 there is a new feature in which you can backup to disk, and then do a Duplicate backupset backup to tape. Then if you need to restore any of that data, you can run the restore directly from the tape as if you had never done a backup to disk backup. Sweet.

Good luck!

 

[TerryPrior]

Thanks for the advice chaps. Here's the latest:
I have my backups set up and running; four separate jobs. For each of the jobs I have created three schedules, one for the full monthly, one for the first differential of the month (which is an 'overwrite' job), and one for all the other differential jobs in the month (an append job). Each job has two backup-to-disk folders, one for the monthly and one for the daily job.
All seems to be running just fine, and I have all my backups to hand if I need to do a restore. However, I have spotted a big flaw in my plan!! On the first day of every month the differential backup will perform an overwrite, meaning that if say, on the 3rd of the month I need to restore a file from say, the 27th of the month, it ain't gonna be there!!
In my old backup to tape method, I had a one month rotation of tapes, meaning that I would always be able to retrieve any file from the last month. With my new method I don't!
I'm guessing that I need some kind of media rotation method, but this seems quite complicated, given that I'm only using disks for backups.

Any thoughts??

Thanks

Terry

 

[SQLBill]

It wouldn't matter anyways, you can only restore a differential backup to the full backup it applies to.

For example, I do:

FULL Backup1
DIFF1
DIFF2
DIFF3
FULL Backup2
DIFF4
DIFF5

DIFFs 1, 2, and 3 apply to FULL Backup1; DIFFs 4 and 5 apply to FULL Backup2. If FULL Backup2 overwrote FULL Backup1, then DIFFs 1, 2, and 3 are useless.

So, if you do a FULL Backup the first of each month or the last day of each month, you wouldn't be able to restore from the 27th anyways.

May 27-DIFF
May 28-DIFF
May 29-DIFF
May 30-DIFF
May 31 or June 1-FULL
June 2-DIFF
June 3-DIFF

Based on the above, the May DIFFs are worthless unless you still have the FULL from prior to those days. If you are ovewriting the FULL, the only DIFFs that are any good are the June ones.

-SQLBill