Virtual Hard Disk Maximum Size?

mphilli7823 · Thu Aug 29, 2013 3:46 pm

I am trying to create a single node virtual hard disk and am unable to create one larger than 10TB. Is this a limitation of the software or am I doing something wrong?

Thu Aug 29, 2013 4:09 pm

Not it's not a limitation of the software. Rather it's something wrong with your NTFS volume you're cryting to create file on. If it gets heavility fragmented fo example you cannot create very big files. What Windows error does StarWind throw on attempt to create the volume?

mphilli7823 wrote:I am trying to create a single node virtual hard disk and am unable to create one larger than 10TB. Is this a limitation of the software or am I doing something wrong?

mphilli7823 · Thu Aug 29, 2013 4:22 pm

It doesn't actually throw an error when creating, however when you look at the properties of the disk, it shows it as a 0 byte disk. There are also no related errors in event viewer. The server I am attempting to create this on, is a brand new 60TB NTFS volume, as a GPT disk. I am uploading a picture of the attached 0 byte disk. Other related servers specs are below

OS = server 2008 R2
Volume size = 60TB formatted
Volume raid level = RAID50
Memory = 32GB
CPU = 2.4 x8
Starwind Version = 6.0.5597 (build 20130527)

mphilli7823 · Thu Aug 29, 2013 4:24 pm

also as for fragmentation concerns, disk defragmenter shows the disk as 0% fragmented. Please see attachment.

mphilli7823 · Thu Aug 29, 2013 6:38 pm

**Update**
I did some more testing, and it seems like the threshold is actually 15TB before it stops working. So I can successfully create a 15TB virtual hard disk image file, but anything bigger and it does not work.

I also have an active case open with support, since we are a paid customer...hoping to find a solution for this soon

james103 · Sat Aug 31, 2013 12:12 pm

I am trying to create a single node virtual hard disk and am unable to create one larger than 10TB. Is this a limitation of the software or am I doing something wrong?

Sun Sep 01, 2013 9:03 pm

Either NTFS is too fragmented and you cannot create big files or you're trying to create LUN larget then NTFS can physically support (16TB) and not 10. Is there any chance you'd provide us with a StarWind log so we could know for sure.

mphilli7823 · Thu Sep 05, 2013 5:11 am

**Update**

So I found the true issue. Server 2008 R2 and below have a max file size of basically 16TB. While server 2012 has increased the max file size to 256TB. See below

"As designed, the maximum NTFS file size is 16 EB (16 × 10246 or 264 bytes) minus 1 kB or 18,446,744,073,709,550,592 bytes. As implemented, the maximum NTFS file size is 16 TB minus 64 kB or 17,592,185,978,880 bytes. With Windows 8 and Windows Server 2012, the maximum NTFS file size is 256 TB minus 64 KB or 281,474,976,645,120 bytes.[4]"

http://en.wikipedia.org/wiki/NTFS

So if you run into this issue and you need VHD sizes > 16TB, looks like server 2012 is the way.

Thu Sep 05, 2013 1:43 pm

Thank you for the update!
I`m pretty sure that people who run into similar problems will find this topic useful.

chrisjacob · Mon Dec 23, 2013 9:03 am

Hi, the maximum size for a virtual hard disk is 2,040 gigabytes. The virtual hard disk provides storage for a virtual machine. In case of a virtual hard disk which is attached to the IDE controller, can't exceed 127 GB.

jeddyatcc · Mon Dec 23, 2013 12:24 pm

chrisjacob wrote:Hi, the maximum size for a virtual hard disk is 2,040 gigabytes. The virtual hard disk provides storage for a virtual machine. In case of a virtual hard disk which is attached to the IDE controller, can't exceed 127 GB.

Chris,

In 2008 you are correct, but in 2012 Microsoft created the VHDX drives that allow up to 64TB. In keeping with the topic. I always recommend 2012 or 2012 R2 for anyone setting up a new SAN on StarWind as the NTFS changes made large drives perform much much better as well as supporting larger files.

Mon Dec 30, 2013 10:51 am

Chris,

In 2008 you are correct, but in 2012 Microsoft created the VHDX drives that allow up to 64TB. In keeping with the topic. I always recommend 2012 or 2012 R2 for anyone setting up a new SAN on StarWind as the NTFS changes made large drives perform much much better as well as supporting larger files.

I`m totally agree with that. WS2012 (R2) has a lot of improvements, which affects the size limits as well, so I`d strongly recommend to consider moving to it.