Video Screencast Help

Looking for Definative solution for using Backup Exec to USB Drives

Created: 21 Sep 2011 | 5 comments
W Harrison's picture

Hi All,

The title sums it up really, I am trying to find the definitive (Symantec endorsed?) solution for using USB removable media/HD’s as a backup destination for Backup Exec that would hopefully operate (from a users perspective) in the same way as backups to tape.

Our normal ‘to tape’ method would involve having (at least) 5 separate backup tapes operating in daily rotation whereby a full backup is performed nightly. No real data volume to be considered where the amount of data would fill a tape resulting in a swap the next day (or the job splitting to Full / Differentials etc.)

Removable media in this instance are devices like the small USB attached HD drives that have now dropped in price and are becoming popular (well have for a while now). As an example, Western Digital have the 'Passport Drive'  range, small, light, single usb lead to connect, not caddy based. Hopefully you get the idea.

What I have found so far is that this as a first point seems to be generally a hot topic, Google responses talk about different solutions where people have got creative with scripts etc to create work arounds, and whilst this may work it still seems to be a fudge fix rather than actual software support.

Backup To Disk or Removable Backup To Disk

My research so far leads me to conclude that...
Backup To Disk folders are always online, can be USB as well as SMB, CIFS, or iSCSI attached. The latest Symantec Hardware compatibility lists example of these as being Buffallo TeraStations, Drobo Drives, Equilogic etc. In other words these things do not fall into the 'small single USB' type drives as mentioned above.

Removable Backup To Disk folders, again can be USB or SATA or eSATA but the most important point being that, when a drive is removed Windows STILL allocates a drive letter to it even though its storage capacity drops to zero. Think of this in terms of a CD-Rom drive, when you take out the physical media, the drive letter/ device stays visible but empty.

Therefore the small USB drives and (importantly - use of) don’t fall into either concept and have to be 'made' to work rather than are supported for this task.

Tests so far
These tests have been performed on a brand new (read 2 week old) server, updated and SP'd untill no more exist - both with Symantec and Microsoft - in this instance working with 3 of these Western Digital drives.

My Results
Again, following various Google results and dismissing anything that needs custom user scripts and schedules to run (remember I'm looking for something that Symantec would recognise and support) I have found that...

Using Removable Backup To Disks folders.

Not supported officially anyway for this method as these drives don’t leave behind a device that keeps its drive letter when there is no media present.

With a single drive letter for all of the drives, the initial inventory and backup work fine. New FLDR000x gets created and the backup proceeds. Swapping the disk then results that the removable backup to disk folder goes offline - manual intervention needed to bring it to an online state again. It also doesn’t recognise that the drive is swapped, the FLDR00x number doesn’t change. Running an inventory against the folder results in an error saying the there is a 'library error magazine missing or not properly installed and does not create the new FLDR00x. Running a 2nd inventory job then adds a new FLDR00x but now it thinks both are online and a backup job fails saying the media server does not exist.

Not really a solution there. Again confirms that a removable backup to disk folder isn’t a solution. Too much user intervention required to keep this thing on track.

Using Backup To Disk folders

 A Device pool had been created with all the Backup To Disk folders added - this was to ensure that the backup job could be 'aimed' at a target that is online. BE then chooses from the online drives as to what to be the final destination. Attempting to create separate jobs that each go to their own B2D folder is impractical (remember end users have to deal with this so if drives don’t get swapped or rotated out of sync then backups wont have a destination)

1st test was to have 3 folders set to the same drive letter but different path (E:\HDD1 , E:\HDD2, E:\HDD3) - when Backup Exec starts (either from a reboot or service restart) with any of these disks plugged in, all Backup To Disk folders come online but with any ‘missing’ folders getting automatically created. eg. Disk1 with Folder E:\HDD1 is attached - after a restart of BE will then the drive also gets E:\HDD2 and E:\HDD3 folders added to it. If this gets un-noticed then when you backup to the drive pool BE will drop files into any of those folders. This then defeats knowing which disk has what data.

2nd test was to have 3 folders again but this time having different drive letters and folders attached to each. So we now have a E:\HDD1, F:\HDD2, G:\HDD3. The big problem here is actually getting windows to fix a drive letter to each disk. The only way of solving this was to have all drives attached at the same time. Problem here being that if any disk gets added or changed for what ever reason, you then have to bring in all of your disks to plug up and check the drive letters. Manageable on creation but again, after that point a simple drive addition or swap is a problem.

With BOTH of these setup with the standard Backup To Disk Folder - if at any point a disk gets removed (and with removed - this is just a simple case of unplug rather than using the windows 'safely remove drive' icon - which in itself is not a good idea) Backup Exec will generate an error message saying a drive has gone offline. Again - leading me to think that the official definition of a backup to disk folder is something that is left online most, if not all, of the time. If Backup Exec handled this 'correctly' then there would not be errors.

Again, on both of these tests - Don’t try to inventory! You cant inventory a drive pool anyway - it doesn’t exist as an option. If you try to inventory a drive that’s off line - then you get an errored job. Effectively creating a 'sea of red' on your job history as you are inventorying drives that are not attached.

Also – lets not go down the GRT based backups as that’s a whole other question!

In Summary,
Are what we trying to achieve here actually achievable? Simplistic backups to easily transportable disks? My instinct at this point in time is not with this version.

Thanks for reading.


Comments 5 CommentsJump to latest comment

pkh's picture

You should use normal B2D folders for your USB disks, not removable B2D folders.  The latter is meant for things like RDX or Jaz drives.

If you have at least BE 2010 R2, then you don't have to worry about assigning drive letters to each of the drives.  BE will automatically know which drive letter to use when a disk a plugged in.  For example, a disk may a E: drive when you define the B2D folder and when you next plug it in, it may be assigned as the F: drive.  BE 2010 R2 and R3 will automatically adjust for this change of drive letters.

Bottomline is that if you want to rotate external disks, use at least BE 2010 R2.  If you are upgrading, upgrade to R3 which is the latest version of BE.

You can read my article on how to rotate disks.

W Harrison's picture

Thanks both for the replies - We have now implemented this and - with the 'files named as folders' fix - seems to be doing its job.

One thing that is still a little concerning though, and this is going back to keeping it simple for end users. I would still like to think that when a job is finished we can issue an 'eject the media' at the end if the job. I know this is physically impossible but to at least get the OS to do a 'safely remove hardware' operation on the USB drive when it gets an eject - this way, by the time the user has acknowledged his backup email they would know that the drive is safe to remove.

One final question on this - I take it you just don’t inventory drives in the drive pool now? You cant send an inventory job to a pool, so the only way is to inventory each drive in turn. The problem with that is you end up with a sea of red failures as it tries to inventory drives that don’t exist.




harsi's picture

Hi Wayne.

We also had a long fight, before we had this up and working the way it would make sense. From what we see it seems that Symantec did not have this usecase in mind.

We used the following tricks to achive what we want.

1.) Don't use Removable B2D folders it will simply not work the desired way.

2.) If you have 3 USB Disks create 1 B2D folder on every drive with a different name (e.g E:\B2D1, E:\B2D2, E:\B2D3).

3.) To prevent that the missing folders are automatically recreated on the USB disks create files with the names of the missing folders on every disk (e.g. on the disk with folder E:\B2D1 create 2 files with the names E:\B2D2 and E:\B2D3).

4.) If you need to keep track of what file is on which USB disk you can use the following script:

Hope this helps.


W Harrison's picture

Hi Harsi,

I must admit - I hadnt even thought about which media contains what yet! So good find on that one!

This seems to enforce further that there maybe needs some more thought given from Symamtec to how Backup Exec works with USB drives.