Suggestions for upgrading from 4.0 to 4.1.

[RivaCom]

We currently have 2 ESX 4.0 Boxes in our current setup.  We have plans to add two-three more esx boxes by end of the year.  However to stay at the same level, I need update the two boxes to ESX 4.1 and the vcenter to 4.1.  Also I have a bad Fiber card in one of the boxes that needs to be replaced.  My questions are:

1. Should I upgrade VCenter first?  I'm assuming it's easy to push the updates through this.  (My only problem is finding a free 64 bit server not in use to load 4.1 on). 
2. If I take the box down with the bad Fiber card(using vmotion to move over all of our vm's), if I then upgrade this box to 4.1, will all the vm's on the other box(4.0) conflict while I vmotion the vm's back to the 4.1 box?  My only worry is we don't have any downtime to play with really so if I can move it all to one box, then all to another, we eliminate all downtime.

[Troy_Clavell]

Should I upgrade VCenter first?  I'm assuming it's easy to push the  updates through this.  (My only problem is finding a free 64 bit server  not in use to load 4.1 on).

If you plan to manage any ESX(i) Hosts, you'll need to be at vCenter 4.1, which is the only version that can manage 4.1 Hosts.

Also,  upgrade path should always be vCenter, ESX(i), VMware Guest Tools, Guest vHardware

If I take the box down with the bad Fiber card(using vmotion to move  over all of our vm's), if I then upgrade this box to 4.1, will all the  vm's on the other box(4.0) conflict while I vmotion the vm's back to the  4.1 box?  My only worry is we don't have any downtime to play with  really so if I can move it all to one box, then all to another, we  eliminate all downtime.

4.0 and 4.1 Hosts can exist in the same cluster with no issues. This also goes for the guests.  And, the 4.1 guests tools are backward compatible.

[Cyberfed27]

Update manager from within vCenter makes the upgrade from 4.0 to 4.1 quite painless.

I upgraded when 4.1 came out a few months back, I had no issues. I did one host at a time and update manager did all the legwork for us.

You should have no problem with the VM's running them on 4.0 and then vMotioning them to a 4.1 box.

The VM's themselves don't really care about the ESX versions running.

[nkrishnan]

Steps:

1) Upgrade the vCenter server to 4.1 and vSphere Update Manager 4.1

2) If you have vSphere update manager 4.1, use host upgrade base line for upgrade the esx to esx4.1. If you configured HA/DRS setup then it will automatically vmotion the VMs from host that is undergoing for upgrade.

Otherwise, VMotion the VMs that resides on the Host that you are planning to upgrade, preferably the host that has bad FC card. So that after the upgrade the host will go for reboot, Instead of reboot , go for shutdown of Server and remove the card.

Nithin