"Media unavailable" with hard drives as media

[fjk 0]

I am using Multiserver 7 and hard drives as my primary storage media, with tapes as secondary archive media. The basic Retrospect approach is to forbid simultaneous use of same media by different scripts-savesets. This is probably a legacy of the days when tape was the only media. It is annoying, but I can get around this by having lots of external disks (or disk partitions). What bothers me more is the frequent inexplicable "Media unavailable" errors. The media disks are fine, have plenty of free space, but the script hangs with this error. I can fool Retrospect by adding another Saveset member to the set, even on the same disk, but it is still very annoying and dangerous. Why is Retrospect so obtuse about the use of disks as the storage media?

[natew 0]

Hi

 

I guess I don't follow you:

You can use one disk with multiple backup sets no problem. Are the external disks formatted as fat32 or NTFS? NTFS is best.

 

Are you using Retrospect 7.0.265? I think it will resolve the media unavailable issue.

 

Thanks

Nate

[fjk 0]

All the disks are formatted with NTFS. I am up to Retrospect 7.0.249 on the backup engine.

 

Nate, you misunderstood my complaint: Can two different scripts simultaneously use the same logical drive as the storage media? Disk drives generally allow simultaneous access by many processes. However, Retrospect treats all media as if it were sequential access media.

 

More to the point: What causes the "Media unavailable" errors? Must I define multiple saveset members, even on the same disk, to ensure that my backup script runs to the end? If your answer is Yes, then why? Retrospect already complicates the disk storage structure by creating folders like:

D:\Retrospect\M-1\1-M-1

Now, to solve the "Media unavailable" error I needed to create a saveset on the same disk:

D:\Retrospect\Retrospect\M-1\3-M-1

 

What is the point of all these subfolders? I still have the same point of failure, my D: drive. I am not spreading the risk of failure, just complicating the placement of backed up disk images.

[michaeln 0]

Hi,

 

 

 

Two different scripts can simultaneously use the same logical drive as the storage media as long they are writing to 2 different Backup Set destinations and the source has 2 different logical volumes (you may see a performance hit if they are logical partitions as opposed to physical partitions).

 

 

 

Valid Example:

 

Source Storage Media (E:)

 

C:\Program Files backing up to E:\Retrospect\Backup Set A

 

D:\Data Folder backing up to E:\Retrospect\Backup Set B

 

 

 

You cannot backup folders on the same SOURCE volume simultaneously.

 

 

 

Invalid Example:

 

Source Storage Media (E:)

 

C:\Program Files backing up to E:\Retrospect\Backup Set A

 

C:\Documents and Settings backing up to E:\Retrospect\Backup Set B

 

 

 

Regarding the folder placement of Retrospect Disk Backup Sets, each Backup Set in it's own folder under the root Retrospect folder to keep the data files separated and organized. The folder structure is 3-tiered and can be complicated although theoretically, you shouldn't have to tinker with the placements of the backup files

 

 

 

If you have an NTFS system, you can look into backing up to File Backup Sets which create single large backup files and might be more manageable if you are moving your backup data around. You will probably want to look into the benefits and drawbacks of Disk vs. File Backup Sets for your setup since each has their own unique features.

 

 

 

I hope this clears up the issue a bit.

[natew 0]

Hi

 

Just to add to Michael's comments if I may:

Retrospect does _not_ treat disks like sequential access devices. Quite the contrary, it treats disks as disks. Random access devices.

 

Thanks

Nate

[flundy 0]

I have the same problem-- Retrospect7 is continually asking for new media even though my disk device is 60-75% empty. Giving it another filename on the same disk allows things to continue. This is *not good* for automating backups.

 

I am using 7.0.265 on Win2k SP4 on NTFS.

[natew 0]

Hi

 

Have you set the backup set to groom out old data when the disk is full or ask for a new disk? I would groom out the old data and go from there.

 

This could also be happening because of a communication problem to the drive. Does it ever sleep or hibernate?

 

Thanks

Nate