As part of private cloud organisation serving small to mid size businesses with various security and compliance demands I was involved in the project building completely new cloud environment, considering technologies of 2016, and streamline the migration of the clients from the original Citrix Xen 6.5 cloud into the new solution based on oVirt and KVM. Here is the article on how to do this link here. For now, let me share something which you do not meet very often neither as a user nor as system administrator.

It is pure Windows insides 101. It is stupid and simple. But it can catch you by surprise.

The story:

After a large VM with additional virtual disks have been exported, converted and imported into the new environment, Windows, booted up in the new setup, decided to shuffle drive name and label assignments. For example, if your drive with SQL data on it used to be labeled as “Drive D:\\” it could become “Drive E:\\” instead. The storage manager of the Windows does not rely or care about FS records or Meta Data stored on the disk itself. As a result of this action the SQL could not start as it could not find the “path specified”. One would think it is a simple problem, just go through the change letter process and reboot the machine (it is Windows after all). When system administrator went through the process he got himself an error stating that the “Parameter is incorrect”

IMG http://www.alexsmirnov.us/wp-content/uploads/2016/07/error-screen.jpg

I must admit, this was the first time I came across such an error myself. But no fear. The resolution in our case was very simple. After Windows (which in our case was Windows Server 2008 R2 x64) booted up, it did not only re-shuffled the letter assignments, it also re-enabled the page/swap file on all of them. If the page/swap file is set on drive, you can not re-assign the letter. The solution is simple:

Step one, remove swap/page file from the drive. One of the many ways to do it is to access “Advanced system settings”. Start file manager, right click on “My Computer” and choose properties. In the top left corner you will see multiple choices, the last of it will be “Advanced system settings”. Click on it. The new tab will open “System Properties” which will look like this:

IMG http://www.alexsmirnov.us/wp-content/uploads/2016/07/system-properties.jpg

Look at Performance and click “Settings”. A new tab will open, which calls “Performance Options”. We are interested in the “Advanced” tab, which look like this:

IMG http://www.alexsmirnov.us/wp-content/uploads/2016/07/performance-options.jpg

• Look at “Virtual memory” and click Change. In the “Virtual Memory” tab you need un-check “Automatically manage paging file size for all drives” at the top and to choose “No paging file” on the disk drive in question.
• Step two, after you OK and accept all the changes, go back to Storage manager and try to change the drive letter. I believe that in some cases, depending on exact version of the Microsoft OS and patch level, you might want to reboot, before changing drive letter as not all versions of Windows support changes in page file without system restart.
• You are done.