How to increase size of differencing disk

– shutdown virtual machine
– start Hyper-V Manager and modify virtual machine’s properties
– select virtual differencing disk to increasing
– click on Edit button and select Merge
– in the Merge action wizard select Merge to new virtual harddisk and put in the the name of the new virtual harddisk
– then you can select whether it will be fixed or dynamically expanding disk
– finish the Merge wizard
– now you have a new virtual harddisk
– modify virtual machine’s properties and change the path for the virtual harddisk to a newly created virtual harddisk
– confirm changes
– now the virtual machine has a new fixed/dynamically expanding disk
– modify virtual machine’s properties and select virtual disk and click on Edit button
– select Expand action and finish the wizard with your values
– start operating system and go to Storage – Disk Management in the Server Manager
– you should see a unallocated freespace in there, so select the existing partition and select Expand disk action
How simple! 🙂
Written on July 30, 2010