I’m looking for some guidance for one of the up-gradation on vSphere 4.0 to 5.1. Here is the setup:
5x ESX 4.0, vCenter 4.0 on Windows 2003 32-bit, Database running on remote SQL 2008 32-bit server, 100+ VMs
As the ESX hosts were previously upgraded from ESX 3.5, upgrade to 5.1 will not support on this because of incompatible partition layout. I’m building a new VM for vCenter on 2008 R2 and going to do fresh install of ESX – one by one (without any downtime) and to keep the DRS and other settings. Here is the upgrade plan:
Few things I need some help:
A lot of the complication in such a migration will depend on answers to the following:
1) When you say no downtime, what do you mean? To switch from Virtual Center on one server to virtual center on another you will require an outage on Virtual Center (the ESX hosts can remain running).
2) Do you require any data from the current virtual center database? If not I recommend completing a completely fresh install of Virtual Center and VUM, then migrating the hosts to this virtual center. This means you can setup the new servers in the parallel, mirror all settings currently in place and complete an organised online cutover (esx hosts can be moved online or between the virtual centers).
3) It is not possible to have an upgraded database with new vCenter online at the same time as the current database and vCenter as the both vCenters will try to control the ESX hosts (remember vCenter itself holds very little data), all data is held in the database.
The methodology is laid out in the following documents: