Migrating the Whole Stack

Goal:  to migrate as many of our varied services and VMs with the least interruption to our customers.  vMotion and storage vMotion whenever possible.  Similar to my previous post here.

Preparation

New vBlock with all storage, compute, network and virtualisation components above was installed fresh so no in-place upgrades were needed as this method is simpler and has less risk.    

Prepare ESX4 migration storage

Storage: Create a VMFS3 datastore on the new vBlock.  Old vSphere v4 won’t recognise the new VMF5 so this is one of many “hops” that mean an extra step to avoid downtime on the VMs.

Prepare ESX4 migration host

Storage: Split HBAs so one is mapped to the old storage for the VMs before migration (unchanged) Then map the new VMFS3 datastore to the second HBA .  This is making the first migration host a “bridge” between the old storage and the new storage, which the VMs step across via vMotion..  

Prepare ESXi5 migration host 1

CPU: put in VMware cluster with EVC mode set to “Neehelam”.  This is so you can vMotion the VMs from the old CPU chipset on ESX4 to new CPU chipset on ESXi5.  This migration host is an extra step to avoid you needing to shutdown the VM to move it to newer CPUs.

LAN: Split pNICs on the 1st ESXi5 migration host by removing one (we have two) from the vDSwitch and assigning it to standard virtual switch and port groups identical to the ESX4 VM networking.

Prepare ESXi5 migration host 2

LAN: Split pNICs on the  2nd ESXi5 migration host by removing one from the vDSwitch and assigning it to standard virtual switch and port groups identical to the ESX4 VM networking.

Steps:

1.  vMotion first batch of VMs to the IBM/NetApp/ESX4 migration host on vCenter4

disconnect migration host from vCenter4 and connect to vCenter5

2.  sVMotion VMs to temporary VMFS3 datastore on the vBlock

configure vBlock vMotion pNIC on ESX4 host to enable vMotion to vBlock host

3.  migrate VMs to ESXi5 migration host with vMotion to get from old CPU to new CPU and vSphere5

4.  migrate VMs to 2nd ESXi migration host with vMotion to get from EVC to access new CPU features 

5.  use network migration wizard to move VMs from standard vDSwitch port groups to vDSwitch port groups with same vLANs.

6.  finally, migrate VMs to “permanent” ESXi5 host 

check cluster settings for VMs  (HA, DRS) in final vSphere5 clusters

7.  reconfigure vMotion disabling vBlock pNIC and enabling IBM/DataCore configured pNIC for vMotion ready for next batch of VMs to be migrated

8.  disconnect ESXi4 migration host from vCenter5 and reconnect to vCenter4.

repeat steps 1-11 until VMs are migrated

Next:  Exchange, SQL Server, and other VMs with RDM storage