Top 5 Tips for Migrating to ESXi
If the message was not clear enough, it is time to move away from the full install of ESX (aka ESX classic). VMware's ESXi hypervisor -- also called the vSphere Hypervisor -- is here to stay. The vSphere 4.1 release was officially the last major release that will include both hypervisors.
In the course of moving from ESX to ESXi, there are a number of changes you need to be aware of that can stump your migration, but none that cannot be overcome in my opinion. Here are my tips to make the transition easy:
1. Leverage vCenter Server for everything possible.
The core management features of ESX and ESXi are now effectively feature on-par with each other when using vCenter for all communication and third-party application support. Try to ensure that specific dependencies on specific host-based communication capabilities can be achieved with a vCenter Server connection or, better still, with an ESXi host directly. A good example of one direct task to an ESXi host would be syslog forwarding; this still can easily be configured directly on an ESXi host.
2. Ensure third party applications fully support ESXi.
There are plenty of applications that we all can use for virtualization. This can include backup, virtualization management, capacity planning, troubleshooting tools and more. Ensure that all vendors fully support ESXi for the products that are being leveraged for the vSphere environment. This also may be a good point to look how each of these tools support ESXi, specifically to ensure that all of the proper VMware APIs are fully supported. This includes APIs such as the vStorage APIs, the vSphere Web Services, the vStorage APIs for Data Protection and more. Here is a good resource to browse the vSphere APIs to see how they can be used both by VMware technologies, and leveraged by third-party applications.
3. Learn the vSphere Management Assistant.
The vMA will become an invaluable tool for troubleshooting as well as providing basic administration tasks for ESXi servers. The vMA is a virtual appliance that is configured to connect to the vCenter Server for a number of administrative tasks to be performed on an ESXi host. Be sure to check out this video on how to set up the vMA.
4. Address security concerns now.
Many virtualization and security professionals are concerned about the lack of ability to run a software-based firewall directly on the host operating system (as can be done with ESX). If this is a requirement for your organization, the best approach is to implement physical firewalls in front of the ESXi server's vmkernel network interfaces.
5. Address other architectural issues.
If there is going to be a fundamental change in the makeup of a vSphere cluster, it may also be time to address any lingering configuration issues that have plagued the environment. While we never change our minds on how to design our virtualization clusters (or do we?), this may be a time to enumerate all of the design changes that need to be rolled in. Some frequent examples include removing local storage from ESXi hosts and supporting boot from flash media (be sure to use the supported devices and mechanisms), implementing a vNetwork Distributed Switch, re-cabling existing standard virtual switches to incorporate more separation across roles of vmkernel and guest networking interfaces, and more.
The migration to ESXi can be easy with the right tools, planning and state of mind. Be sure also to check the VMware ESXi and ESX information center for a comprehensive set of resources related to the migration to ESXi.
What tips can you share on your move to ESXi? Share your comments here.
Posted by Rick Vanover on 06/14/2011 at 12:48 PM