Kevin Holman's System Center Blog

Posts in this blog are provided "AS IS" with no warranties, and confers no rights. Use of included script samples are subject to the terms specified in the Terms of UseAre you interested in having a dedicated engineer that will be your Mic

Logical Disk Availability is critical – what does this mean?

Logical Disk Availability is critical – what does this mean?

  • Comments 8
  • Likes

You might have noticed a logical disk availability monitor, being red on some of your systems.

 

image

 

One of the challenges with this monitor – is that it has really good product knowledge, but the state change context doesn’t give us much to go on:

 

image

 

“BAD” is not enough information really to go do something to a production server.

 

If you look at the product knowledge – which is pretty good – it mentions

  • Related physical disk has been removed
  • Physical disk has become corrupt (for example; bad sectors) or inoperable
  • Problem with physical disk driver

As to resolutions:

  • Open the Disk Management snap-in.
  • Rescan the disks and then reactivate any disks with errors.
  • Resynchronize or regenerate the volume as necessary if the disk was a member of a mirrored or RAID-5 volume.
  • Run chkdsk on any reactivated volumes.

But what if you didn't see any problems?  Then what?  It’s not like we are going to run off and run a chkdsk on a production server if we don't see anything wrong or know about any previous disk issues.

 

At that point – it is good to know what this monitor is actually doing.  If you look at the MP in the XML, or follow the Monitor > MonitorType > DataSource in the Authoring Console, you will see this monitor runs a script every 5 minutes (Microsoft.Windows.Server.LogicalDiskHealthCheck.vbs)

While the script does MANY checks… the primary driver of “BAD” state is a single item – a WMI query to the Win32_LogicalDisk class to see if the Volume is marked as dirty.

You check this yourself:

  1. Open WBEMTEST
  2. Connect to root\CIMV2
  3. Select query, and paste in:  “select * from Win32_LogicalDisk where (DriveType=3 or DriveType=6) and FileSystem != null”  (no quotes)
  4. Whichever drive letter is red – select that one by double-click.
  5. On the right side – click SHOW MOF
  6. Scroll all the way down in the list to “VolumeDirty”

If VolumeDirty = True, then this monitor will be “bad”.

What this means is – at some point this volume got a NTFS error, or was removed from the OS in a critical manner.  It *requires* a Chdksk /f to be run against this volume to restore VolumeDirty to a FALSE condition.

So – if you see these – you can double check this by running the simple WMI query… and then just schedule a Chkdsk on the volume during the next available maintenance window.

Comments
  • Hi, a chkdsk does miracles on this error!

  • Hi,

    How can i generate a performance report for logical disk - Avg. Disk sec/Write per day?

    thanks

    Raj

  • Hey Kevin, what would cause this property to return bad if there is no volumedirty in the MOF and the the property is "null" and the machine is a virtual win2008r2 server?

  • I would require disk space report like total space free space and % free space in report. Is it possible to do that? My management is eating my head to get this from SCOM. Please help me here.

    Any help would be really appreciated.

  • Any help please for disk space report in the format like Total space, free space and % free space from SCOM 2007 R2

  • I want the old Monitor back. At least it could detect whether the drive is there or not. I have tested this tons of times and it does not work!

  • @Jason - what do you mean?  Give me a scenario.  I don't think we changed anything here.

  • Hello,

    I ran the WBEMTEST with the query and nothing is showing red but the Monitor is still flipping to Critical Alert every 2-3 days....

    Any other step to locate the error?

    Thanks,

    DOm

Your comment has been posted.   Close
Thank you, your comment requires moderation so it may take a while to appear.   Close
Leave a Comment
Search Blogs