Upgrading an undersized vCenter server

[MariusRoma]

A vCenter server for a small farm (4 hosts and about 200 VM) was originally installed on on undersized hardware and now must be moved to a more appropiate host.

I see two options, implementing a dedicate host or a virtual appliance.

• If I select a dedicated phisical host and perform the procedure described on page http://kb.vmware.com/kb/5850444, how much RAM should I implement, given the same host must act either as vCente and Update Manager? Based on the documentation I would say 4 GB, but based on my experience I am not sute 4 GB are enough: can anybody please suggest the right memory sizing?
  
• If I select a virtual appliance, can I migrate the cuttent vCenter from the currend physical host to the virtual appliance?
  
  • Given I can migrate the current vCenter to a virtual appliance, what are the disadvantages of implementing a virtual appliance instead of a physical host?
    

• As a very last chance, can I instead use VMware converter to convert the current vCenter to a VM and install it inside the vSphere infrastructure?
  

Regards

marius

[JCMorrissey]

Hi,

I would say given your small number of items that you'll probably have in your inventory 4gb should be enough(even including VUM - from

http://pubs.vmware.com/vsphere-50/index.jsp?topic=%2Fcom.vmware.vsphere.install.doc_50%2FGUID-67C4D2...

Hardware requirements VUM -

Minimum Hardware Requirements

Hardware	Requirements
Processor	Intel or AMD x86 processor with two or more logical cores, each with a speed of 2GHz
Network	10/100 Mbps
	For best performance, use a Gigabit connection between Update Manager and the ESX/ESXi hosts
Memory	2GB RAM if Update Manager and vCenter Server are on different machines
	4GB RAM if Update Manager and vCenter Server are on the same machine

) - there is a nice breakdown too in the table enclosed regards memory sizing depending on object numbers in the inventory

http://pubs.vmware.com/vsphere-50/index.jsp?topic=%2Fcom.vmware.vsphere.install.doc_50%2FGUID-67C4D2...

The appliance does come with limitations, main one is no VUM support take a look at

http://www.yellow-bricks.com/2011/08/10/vcenter-appliance/

Personally haven't used it there does some seem to be some scalability issues, also no direct migration path. As such you'll deploy the appliance and manually add the hosts back in. Given your small number that shouldnt be too big a problem. The bigger issue is scalability in terms of number of VM's supported. vCenter "traditional" would be the recommended route

Many tx

[a_p_]

As a very last chance, can I instead use VMware converter to convert the  current vCenter to a VM and install it inside the vSphere  infrastructure?

What you consider as "last chance" is actually something I would consider as a "preferred choice". If you do have shared storage and vMotion/HA in place, running a vCenter Server as a virtual is the recommended option.

André

[MariusRoma]

Do you mean implementing a Windows Server 2008 R2 VM hosted by one of the ESXi hosts and running vCenter?

I could provide a large amount of (virtual)RAM and (virtual)CPU.

In my opinion it could be simpler to implement, do you see any critical issues?

Regards

mario

[a_p_]

Basically you will benefit from running vCenter Server as a VM in multiple ways. Firstly you can assign the resources you need and adjust them easily if required, secondly - in case of a hardware failure - you can run vCenter Server on another host (provided you have shared storage). With HA in place you can even automate the restart of the vCenter Server VM in case of a hardware failure. And last but not least you will save on power and cooling as well as cabeling/switch ports.

André

[MariusRoma]

Let's imagine a possible scenario.

• I take the current vCenter offline while the ESXi host go on working.
  
• I run VMware converter to convert the server to a VM hosted by one of the ESXi hosts
  
• I connect the netwotk interface to a switch not connected to the Internet and I ensure that the converted vCenter works fine
  
• If I find any kind of problem I try to correct it
  
• If I think that the converted vCenter is OK I just connect to a switch connected to the general LAN, as it was the original vCenter
  
• At this point the converted vCenter go on performing the same tasks as the previous physical one
  
• If anythong goes wrong I reconnect the original physical vCenter and nothing changed
  

Am I missing any relevant step?

Should I perform any action on the converted vCenter, besides re-activating Windows?

Now, let's consider some additional issue:

• If the converted virtual vCenter is hosted by a host and the host fails, is HA suppoded to go on working?
  
• In other words, can I presume that if the node hosting vCenter fails the vCenter VM is moved to another node and restarded?
  
• If for any reason the vCenter server does not restart on another node, what management features are disabled?
  

Regards

marius

[a_p_ · Accepted solution]

The steps you mentioned should work ok. After converting the VM, make sure you reconfigure the IP settings and remove/delete any hardware related drivers and services which were installed for the physical host, then install VMware Tools. I'd further suggest you shutdown the vCenter Server services and SQL-Server (in case of a local installation) on the physical host before you start the conversion.

Regarding HA, vCenter is only required for HA configuration. HA itself works on the hosts, independently of vCenter Server. While the vCenter Server is powered off the VMs will continue to run and just features like vMotion, DRS, ... which are initiated by vCenter Server won't be available.

I assume you don't have any other features like View Composer, ... installed on the vCenter Server!?

André

[MariusRoma]

Thank you for the whole of your support and hints.

I performed a test using VMware Converter to virtualize a Windows Server 2008 R2 server hosted by an hardware identical to the one hosting my vCenter.

Conversion was fine, but after rebooting the converted VM the network card was lost, I presume for driver incompatibility issues.

I had to add a new virtual NIC and to assign the same address as the lost one.

Now my converted server (thai is nor my vCenter...) works fine.

If the same problem will occur while converting my vCenter server (i presumwe it will) can it create problems to the vCenter itself?

I don't think so, because it sounds like replacing a NIC with a different one, but I would be happy to read it won't...

Regards

marius

[a_p_]

... the network card was lost,

You should have the option to select a network adapter in the converter wizard. I'd suggest you select an e1000/e1000e adapter, which should be detected by Windows out of the box. Since this is a new adapter for Windows you will have to reconfigure the network settings. What you may want to do, is to set the MSSQL and vCenter Server services to manual or disabled on the source machine and stop them. This way you will be able to cleanup the VM, reconfigure the network and install VMware Tools before the services start for the first time after you re-enable the them again.

André