In order to recover the virtual machine, I had to remove all the snapshots on the virtual machine, but the process hang up after 3 to 4 times I tried. You may able to perform this with command and if you are lucky enough, you should able to remove the snapshot by using command. Alternatively, you can also clone a new virtual disk image contain the delta file changes to a whole new virtual disk by using vmkfstools command. This will require quite some times for you to recover the situation mostly the business will not able to wait and it is no guarantee that the recovery will fully work as we expected.

For my case, the quickest way to recover this is to clone the entire virtual machine to a new datastore that have the disk space you require and power it up immediate after the clone. We double checked the entire virtual machines mount point and services, everything require and last file transaction is available without any issue and back to production. Now I will have my sweet time to slowly investigate the failure to remove snapshots on the virtual machines. Well, is not necessary the method I am using here is the best, but I would like to share my personal experience in the critical production time, you may wanna consider the best option to recover the production virtual machine as soon as possible.

Due to certain requirement, you may need to clone a snapshot taken sometimes ago and you can make as many copies as you need.

This guide show how to making a clone from a snaphot on VMware Workstation 6.5.

Note: The snapshot MUST BE from a virtual machine that is powered off.

Open VMware Workstation 6.5, click on VM tab, click Snapshot, click Snapshot Manager or CTRL+m.

Click clone.

Click Next on Clone Virtual Machine Wizard.

Click Next Clone from The current state in the virtual machine.

Click Create a full clone and Next.

There are 2 types of clone:
# A full clone is an independent copy of a virtual machine that shares nothing with the parent virtual machine after the cloning operation. Ongoing operation of a full clone is entirely separate from the parent virtual machine.
# A linked clone is a copy of a virtual machine that shares virtual disks with the parent virtual machine in an ongoing manner. This conserves disk space, and allows multiple virtual machines to use the same software installation.

Enter Virtual machine name, Location and click Finish. You’re done!

I’m sure you will ask making a clone from a snapshot for VMware ESX Server. Just do a live clone and revert to snapshot taken or you may refer to VMware Communities Forum.

Enjoy!

I did a quick test and I would like to share my personal review about Citrix XenServer 5.0:

Personally I think network speed is fast compare to VMware ESX. I have a physical 1Gbps NIC network speed and I can get 2Gbps network speed after install XenTools on Windows 2008 server but require 2 times reboot(SuSE Linux require 1 reboot). Anyway VM guest shutdown and reboot process is faster than VMware ESX.

I was try to install SuSE Linux 10 using 4 ISO CD (both NFS or CIFS), the Citrix XenServer always give me an error “The VM rejected the attempt to detach the device xxxxx refusing to close” when switch ISO CD1 to ISO CD2. You have to extract 4 ISO CD into one single location to make it work or copy ISO to local storage(provider you have enough local disk space).

The enterprise product should not have similar issue and this is not make sense at all.

Anyway, you can try alternative way using “Install URL” instead of using ISO Image once you have extract ISO CD into single folder on your web server.

Install URL: http://xx.xx.xx.xx/inst/10/32/SP2/ALL
Advanced Boot OS Parameters:
console=ttyS0 xencons=ttyS hostip=xx.xx.xx.xx/24 gateway=xx.xx.xx.xx dnsserver=xx.xx.xx.xx

Please make sure your have correct IP, gateway and DNS setup properly else you will getting error during installation.

Add and remove any disk/storage on Window 2008 or SuSE Linux 10 no downtime or reboot required. The VM guest OS will detect automatically.

Convert to template and VM clone features which are another features behind VMware ESX.

Once you have converted to template, you won’t have another way to reverse back as VM guest machine. It’s one way operation which you will received a warning before convert to template as show below.

Right click VM guest, and click Copy VM will do VM cloning but require downtime. The Copy VM feature is disable during VM guest is power on.

Overall, I would said VMware ESX still my first choice.

This had been really impressed and simplify the day to day task for our operation perspective. We know the snapshot manager is the option do help when we apply changes to the VM, but some how for critical machine, we do need to have clone another set of VM in case for roll back purpose.

Previously, we had to shutdown the VM and do a cold clone, that is really time consuming and provide down time to the business. In order to persuade with the 30 mins down time is not as easier as we thought due to the business operation perspective. Now, we can do a Live Clone without shutting down the production, and that will really help us during the test environment as well as patching activity. This features is really benefit for us as we run the ESX and VMs on the High Availability environment which host critical application to our business.