2 replies to this topic

[kmolloy]

Looking for any assistance for an issue we have been having. Here is some background on what we are doing that is generating this error consistently:

We have a piece of server hardware that does automated backup of Database files every 15 minutes. The vendor designed the system to do backups as .img files in order to allow certain restore features. Many of their clients (including my boss) preferred to also have copies in zip format, so the vendor recommended imdisk as a tool to mount these images so they can be zipped. We have scripted mounting the images, zipping with 7zip, then unmounting the image. My boss is a little over zealous with her backups, and also wants this script to run every 15 so that we have zipped copies of the data on the image for easier access (Also for storing backups as the .img files are ~25GB and the .zips are only ~2.5GB). This all works fine for a number of times, then all of a sudden we start getting "Error creating Virtual Disk :The parameter is incorrect" both when running the script or mounting the images through the control panel applet. Restarting the server resolves the issue, but again after running through a number of times (I would guess about 50-60 times) the error returns. Are there any known issues with running imdisk repeatedly? My first guess was mounting/unmounting repeatedly was creating a system resource issues, but I do not see any issues.

We are running the x64 versions of imdisk in Server 2008 R2. Any insight or ideas would be appreciated. Imdisk is the only utility I can find that fits our needs and I need to find a way to make this work reliably.

[Wonko the Sane]

I don't get it.

You do not need to mount a .img to compress it.

You mount it if you want to compress it's contents (file by file).

Why don't you simply run ANOTHER app that makes a copy of the "source" database files and zips them?

Or, alternatively you could use a tool like EXTRACT:
http://www.winimage.com/extract.htm
or the MTOOLS:
http://reboot.pro/14354/

Have you tried opening the .img file in 7-zip?

(these are all methods to access the contents of an image WITHOUT having a running service and mounting them).


Wonko

[Olof Lagerkvist]

Are there any known issues with running imdisk repeatedly? My first guess was mounting/unmounting repeatedly was creating a system resource issues, but I do not see any issues.

Yes and no. ImDisk can handle a maximum of 64 virtual drives (or was it 63?) at one time. After you have dismounted a drive, it might take a while before all handles are closed etc so that the device object can be removed. Until that time, a device number is occupied by a remove-pending device which counts towards the maximum drive limit. I would guess that you reach that limit reasonably quick if you mount-dismount frequently in combination with something on the host system that holds handles to disk devices for a long time.