Migration of VMs to New SAN and ESX Servers farm

[Shakey]

Hi,

I have not carried out migration of VMs before therefore I need some help with few questions.

Customer already has existing V13 3 x ESX 3.0.x with 1 x Virtual Center Management connected to SAN. They going to install new SAN and install 5 x new ESX server farm and have VC as virtual.

1. Does VMware recommend have VC as virtual or physical box? and by having virtual does have any impact, assuming that in this case we have 5 ESX servers.

2. Do you suggest to install full Microsoft SQL 2000 or use deafult MSDE for license server? and also Micrsoft SQL 2005 express edition support for license server?

2. I need migrate existing VMs from old SAN to new datacenter and SAN. What is the best way? requirement is to keep the down time to minimum during the migration.

3. We are looking to use the existing licenses therefore what would be the best way to build the new 5 ESX servers? does VMware provide one off license key to support the migration phase i.e 2 or 3 months?

4. I am bit confused about VC licensing, my understanding is that you buy 1 VC license and can manage any number of ESX servers within the same farm, is this correct?

5. Any practices you may have to offer in this.

Thank you

Kind regards,

Sultan

[depping]

1) there's a complete pdf on this site about a virtual VirtualCenter server, works like a charm but there are some restriction

2) i always try to use the full version of sql if possible cause the msde is not supported in production environments as far as i know

2) Shutdown VM -> Migrate and select a different datastore. that is if both storage devices are connected to at least one esx server at the same time

Duncan

[Nautilus]

1. VC ca nrun as a VM

2. MSDE is not supported for production environment, only for test

2. shutdown vm, move vm, power on vm (best way)

3. its better way when you talk with vmware. But you can get eval licances for (i think) 40 Days

4. yes, you have to buy 1 Virtual Center management Server License

5. ?

But, i think its good for you and for your project when you read some vmware documents, than you will be get better information as this "quick and dirty" infos.

I hope this helps you

Nautilus

[Shakey]

Thanks for reply, please correct me if misunderstand. Connect one of the existing the ESX server to new SAN LUN where the VMs is going to stored and you are suggesting to use the VM -- Migrate, does this uses VMMotion?

Thanks

Sultan

[esiebert7625 · Accepted solution]

>1. Does VMware recommend have VC as virtual or physical box? and by having virtual does have any impact, assuming that in this case we have 5 ESX servers.

There are pros and cons to both, in general VC will run well as a VM. The pros include being able to leverage the High Availability feature for VC, so if the host server fails VC will start on another server. The cons include not being able to cold migrate the VC VM because you need to shut it down to cold migrate and when VC is down you can't use cold migrate. No big deal really.

Running VirtualCenter in a Virtual Machine - http://www.vmware.com/pdf/vi3_vc_in_vm.pdf

VirtualCenter Technical Best practices - http://www.vmware.com/pdf/vc_technical_best.pdf

>2. Do you suggest to install full Microsoft SQL 2000 or use deafult MSDE for license server? and also Micrsoft SQL 2005 express edition support for license server?

I think you mean for the VC db server, the license server does not require a database. I would not use MSDE if it is a production environment, SQL Express is pretty much the same as MSDE and is not supported. I'd go with the SQL 2000 install.

SQL 2005 Express edition support - http://www.vmware.com/community/thread.jspa?threadID=67175

SQL 2005 support - http://kb.vmware.com/kb/6565318

>2. I need migrate existing VMs from old SAN to new datacenter and SAN. What is the best way? requirement is to keep the down time to minimum during the migration.

You can use VMware Converter for this, it may not be the fastest solution though. Using a copy program like FastSCP and then vmkfstools -i is a good alternative.

>3. We are looking to use the existing licenses therefore what would be the best way to build the new 5 ESX servers? does VMware provide one off license key to support the migration phase i.e 2 or 3 months?

Just use eval licenses, they are only good for 30 days they you will need to keep renewing them. When requesting additional licenses they will not send you more then one so you will need to use a different email address and register with it instead.

>4. I am bit confused about VC licensing, my understanding is that you buy 1 VC license and can manage any number of ESX servers within the same farm, is this correct?

Yes this is correct, all ESX versions come with a VC agent license, the Server license is separate and is good for any number of hosts.

5. Any practices you may have to offer in this.

[esiebert7625]

Cold migrate does not use vmotion, you must shutdown the VM to do this. When vmotioning you are simply moving a VM from one ESX host to another not changing the location of the VM's files. Moving from one storage to another storage while the VM is running is called Dmotion and is currently not supported between VMFS3 volumes (only from VMFS2 to VMFS3). The cold migrate will only work if both servers are being managed by the same VC server.

[Shakey]

Thank you very much for your replies very useful and will have read at the pdf documents. Last questions, what do you mean by the VMKfstools -i? I assume when I copy the whole VMs folder from old SAN to new SAN, On the new ESX server box via serivce console do I need to run VMKfstools -i to import the copied VMs.

Sultan

[esiebert7625]

You should never just use SCP to copy a VM from one VMFS volume to another. It will work but you will suffer performance degradation as a result. Using vmkfstools -i imports the vmdk file into the vmfs3 file system and allocates all space at once before it copies the data. Using scp allocates the space while copying which can lead to VMFS fragmentation and poor disk performance. What I normally do is SCP the virtual disk to a temp directory on my vmfs volume and then use vmkfstools -i to copy and import it into my VM's directory.

[Shakey]

Sorry, are you able to give me an example of vmkfstools -i (copy and import) full command. I am just testing this right now as I have ESX servers in VMs for test purpose only.

Thank you - Sultan

[esiebert7625]

Sure, I have one in the below tip (method 3), the basic syntax is vmkfstools -i <source disk> <destination disk> You only need to specify the non-flat vmdk file, it automatically copies both for you.

http://vmware-land.com/Vmware_Tips.html#VM1

[esiebert7625]

Also the System Config guide is a whole appendix on vmkfstools...

http://www.vmware.com/pdf/vi3_301_201_server_config.pdf

[Shakey]

Thank you ever so much for all this information. This will be my first main VMware project in few weeks time.

Just to be clear, vmkfstools -i copy / imports the hard disk but I still need to create new VM but using exisiting HD under the new ESX server, this is correct?

Sultan

[Shakey]

One other thing which came to mind was about the swap file size. If you have ESX servers with 4 or 8 or 16 or 32, what is the recommended swap file size for each memory configurations?

Thanks Sultan

[esiebert7625]

Two ways of doing that, you can either just copy the vmdk files to the destination ESX server temp directory, then create a new VM with a small hard drive, then delete the drive (you can't create a VM without one) and then use vmkfstools -i to copy the disk file into the new VM's directory, once complete edit the VM's settings and add a new hard drive and tell it to use an existing disk and then browse to your disk file. Or you can copy all the VM files from the other server to the destination server by creating a directory for the VM on your VMFS volume, then run vmkfstools to make a copy of the disk file in that same directory, then register the VM on the ESX server, edit the settings, remove the existing hard disk, add a new one and browse to the disk file you created with vmkfstools

[esiebert7625]

Good thread below that talks about swap file size...

http://communities.vmware.com/message/484615#484615

[Shakey]

Any thing I have to do to register the VM on the ESX server? if so where.

Through UI there is no import feature to bring in existing VM option.

Sultan

[esiebert7625]

Yeah they don't make it very obvious, below is the procedure...

How do I register an existing Virtual Machine in VirtualCenter? - If you have an existing VM that was removed from VirtualCenter and just need to add it back in then follow the below steps

• Select the ESX server in the VirtualCenter that the VM files are located on

• On the summary tab right-click on the datastore that the VM files are located on and click "Browse Datastore"

• Select the folder that the VM files are located in

• Right-click on the VMX file for the VM and select "Add to Inventory"

• Select a name and location for the VM and click Next

• Select the Host or Cluster for the VM and click Next

• Select a Resource Pool and click Next

• Click Finish and the VM will now appear in VirtualCenter

[Shakey]

Thank you once again. I think I am done for tonight busy day tomorrow.

All worked so far! I will try adding the new tomorrow.

Good night.

Sultan

[Shakey]

Hello,

Sorry for the delay. I have tried adding the new migrated VM back into the VC as your suggested works fine. I can also power on the machine no problem but when try to open I get access denied message, see the attachment. Any idea, why I am getting this message.

Kind regards,

Sultan

[Nautilus]

just read it

connect with puty to the host

cd /vmfs/volumes/name-of-your-san /myVM

chmod +x WINXP_TMPL.vmx (or you can give full access for all with

chmod 777 WINXP_TMPL.vmx

Best regards

Nautilus