How to decrease size of thick disk?

[atariguy]

I am trying to fix a mistake I made a couple of years ago, when I set up my first VMware ESXi 4 server. I have 2 VMs hosted on it, one of them is an Exchange server running on Windows 2008 R2, and the other is a Sonicwall virtual email security appliance.

I had 1.82 TB of disk space available, so I made the largest possible datastore I could and allocated it between the 2 VMs (the Sonicwall virtual appliance got 82 GB and the Exchange server got all the rest). This let me with 6.50 GB free.

I am currently evaluating the Trilead VM Explorer backup program, and have found that 6.5 GB is not enough free space if I want to reliably do hot backups because of the space the snapshots take.

It turned out I was only using about 25% of the space allocated for the Exchange server, so I shrunk the partition down to about 1 TB using the Windows 2008 R2 disk management tool.

However, I have been unable to find a way to similarly shrink the datastore. Is there an easy way to do this? Since it is hosting our Exchange server, minimal (if any) downtime is important.

[onoski]

A thick disk drive is fully committed and as far as am aware this can't be reduced.

However at your own risk have a read through this: http://professionalvmware.com/2009/09/how-to-shrink-a-vmdk-file-in-esx/

[Sawkat]

try doing a svmotion and change the type from thick to thin and then use vmkfstools

[a_p_]

Unfortunately you need to use e.g. VMware Converter to resize/shrink a virtual disk. This however requires downtime, which - assuming you don't have another datastore to convert (V2V) the VM directly - could be quite long.

André

[atariguy]

Would it be possible to use Trilead VM Explorer to replicate the VM to another server and have it convert it to a thin disk while it's at it?

[atariguy]

I do have another ESXi host I could move it to, which has a datastore that has enough space to fit the scaled down version.

I've done some looking into the Standalone Converter (looks like 5 is the newest version, so that's what I downloaded), and it appears that if I install it on the VM that I want to change, I might be able to do a P2V conversion to a new VM on the other host without any downtime. Is that correct? (This is an Exchange server running on W2008R2 64 bit).

Or, it looks like the other possibility is to turn it off (perhaps overnight) and do a V2V. That might actually be safer, but probably take longer.

Any suggestions, pros and cons, etc. for either way?

Thanks!

[atariguy]

I asked Trilead support this question, and they suggested I use vmkfstools, so I guess the option of using VM Explorer is out.

[a_p_ · Accepted solution]

Although it may require downtime, I'd go with the V2V conversion, especially for a system with an application server like Exchange. As a side note, you can speed up VMware Converter 5 significantly by disabling SSL (see http://kb.vmware.com/kb/2020517).

André

[atariguy]

Thanks. About how long do you think it would take for the conversion to happen? The virtual disk that I'm shrinking is currently set at 2 TB, but contains less than 300 GB of actual data. I think both hosts, as well as my PC where the Converter program will be running, are all on the same switch. And I will turn off SSL.

[a_p_]

I can't tell you for sure, but with a 1 GBit/s connection, I'd guess it may take something between 2 and 3 hours (maybe less!?).

André

[atariguy]

The KB article you referred me to about disabling SSL refers to a file called converter-worker.xml. I do not see that file on the computer I will be using. However, I do see a file called coverter-client.xml which does contain a <useSsl> element. However, in the top of the file it says it's an example file. Do you think that is the right place to change it?

[a_p_]

The file should be at the location mentioned in the KB article. Do you see the directory at all? If not you may need configure your Windows Explorer to show hidden files and folder.

André

[atariguy]

I do see the folder, but that particular file is not there. I'm wondering if it's because I've installed the client version, rather than the client-server-agent version. I assumed that since the VM will be off, there is no point installing software on it directly.

[a_p_]

I'm wondering if it's because I've installed the client version ...

Yes, that would explain it. The file is created with the server installation. I'm not sure about the default (SSL or not SSL) for the client version, but I think it's only an issue with the server version, so this should be fine.

André

[atariguy]

Well, I got it done. It only took a couple hours to move/convert it to another ESXi host, but when I went to move it back, the time estimate went up to 24 hours, so I cancelled it. I ended up using Trilead VM Explorer to replicate it back (hoping that would be faster), but that ended up taking nearly 2 days!

When I moved it off originally, I could see that it was using nearly the full 1 Gbps available, but when I brought it back it only used a small fraction of that. Why would that be? I'm guessing that was the cause of the huge time difference.

[a_p_]

Glad to see you got it done.

I can't really explain the time difference. Since the network seems to be ok (at least it worked well converting it the first time), I'd probably take a closer look at the disk subsystem. What type of storage do you have? Disk types (SAS/SATA), disk speed, number of disks, RAID level, RAID controller with or without write-cache (i.e. write-back mode enabled)?

André