Saturday, February 27, 2010

Hot vs Cold cloning

It’s not about human cloning, ok?
It’s about VMware cloning. VMware, which is the new project i have to finish in few months – virtualizing almost every server we have. So, there are 2 ways to clone a physical machine:

- cold cloning – you boot the machine into a VMware converter ISO, operating system is off, no activity on the hard drive, and you get to clone everything just the way it was just before you shut down the machine. Configured IP address on the VMware converter that boots up has to have access to the VCenter or ESX machine in order for things to work.

- hot cloning – the physical machine is booted into the operating system it currently has. You start VMware converter on another machine. This machine has to have access to both physical machine that you want to virtualize and the VCenter / ESX machines, and they have to be visible to each other too. Bad part about this method is that the machine is not turned off, i mean, the operating system is not turned off, then hard drive might change during cloning, and data loss occurs.

Unfortunately, cold cloning is not working for me at all. It gives all kinds of errors. Yesterday i tried cold cloning again…made some changes and tried again..and so on, till i finally decided to close all services on the server and then do a hot cloning. I looked the error on VMware KB and they said it’s something related to network problems – something like the NICs are not configured with automatic negociation, ..or something like that. I made sure every NIC from ESX or the physical machine i wanted to virtualize were both auto-negociating speed and duplex and tried again. But i had the same problem. After closing every service on the machine, so no hard drive changes during cloning, and my computer at work coordinating the conversion from the VMware converter standalone, everything work great. Started everything at around 10pm. At 6:30 am i had almost 400GB of virtual machines (2 of them) converted from physical to virtual. All i had to do was changing IP addresses for the new VMware adapter on the host, and installing VMware tools. That was all. BTW, physical machines were Windows 2000.

Anyway, after a good night sleep, when i woke up in the morning at 7am, both machines were converted. No errors, too.

No comments:

Post a Comment