My on-premises VM already uses D:, can I still move that VM to Azure?

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Rob Waggoner

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Question:

I am considering moving some of my existing VMs to Azure, but I see that Azure already uses the D: drive.  My application server requires the use of D: drive.  Can I still move my workload to Azure?  If so, how can I prevent this drive letter conflict?

Answer:

Yes, Microsoft Azure uses the D: drive as a Temporary Storage drive and places pagefile.sys on the D: drive.  If you need to use D: for your application server, you can move pagefile.sys from D: to another drive.  Here is a screen shot of Disk Manager showing the default configuration.

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You can follow the instructions here to move the location of pagefile.sys to a different drive (letter).  Once you complete the move, your setup should look similar to the setup below.  Notice that the instructions do not delete the “Temporary Storage” drive, we just change the drive letter of “Temporary Storage”. 

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So why do we do this on Azure?  We place pagefile.sys on this temporary drive because we do not replicate the temporary drive for LRS or GRS redundant storage.  There’s no reason to replicate pagefile.sys, and by not replicating it, we reduce a significant about of replication overhead.

Until next time,

Rob