One of the most repetitive questions that I get asked is which version of vCenter Server should I be using. This obviously is based on the decision between using the vCenter Server appliance (VCSA) introduced with vSphere 5.0 or the trusted and proven vCenter Server on Windows.
It has been general knowledge that the vCenter Server appliance, since its introduction has lacked features to that of its Windows counterpart. With vSphere 5.5 the vCenter Server appliance has come a long way, it supports all solutions that integrate with vCenter Server (vCD, vCOPs, SRM, VUM etc) but is it production ready? I can confidently say yes but will it meet your requirements?
The easiest way to answer this is to follow these steps
Step 1 – What features are missing?
This used to be a bigger problem than it is today. The only things we are missing at this point with the vCenter Server appliance are Linked Mode, vCenter Server Heartbeat (EoA) and SQL Server support. If you need any of these features, its game over, stick to the vCenter Server on Windows.
Step 2 – Figure out the scale limits. The embedded database that is preinstalled with the vCenter Server appliance will support an inventory size of up to 100 vSphere hosts and/or 3,000 Virtual Machines when sized appropriately. If your scale requirements are higher, is an external database an option? You can use an external database to meet the vCenter maximum scale of up to 1,000 vSphere hosts and/or 10,000 Virtual Machines. However the only external supported database with the vCenter Server appliance is Oracle. If you are a SQL Server shop, the vCenter Server appliance is not for you.
Step 3 – Do you have any operational/environmental/regulatory requirements?
The vCenter Server appliance is delivered on a SUSE distribution, however VMware does not update the OS level patches and hotfixes as they become available, VMware publishes release updates containing the accumulated patches and hotfixes and in the case of vCenter Server, this could be 6 months out (we do deliver critical security patches (ie Heartbleed). Other considerations include 3rd party agents, tweaking Linux settings and removing things aren’t supported. Backup requirements, too, are sometimes a challenge (if, for instance, the database team requires that databases be backed up separately to the virtual appliance).
Step 4 – Using the appliance, today, still requires a certain amount of Linux expertise.
Many customers assume that we’re further down the “lock it down and hide Linux” road than we actually are. I’ve spoken to customers who were excited about moving to the vCenter Server appliance because “we don’t have to worry about the OS, any more.” This may not be true if you get into a troubleshooting scenario or require additional configuration settings.
Step 5 – Migrating to the vCenter Server appliance
Ok so you may have survived the first few steps and ready to adopt the vCenter Server appliance but getting to it maybe more of a challenge. We do not have any migration/data tools available to move your vCenter Server on Windows to the vCenter Server appliance. You will have to deploy a fresh vCenter Server appliance and manually recreate the configuration and manually move the vSphere hosts over to the new vCenter Server appliance. Do you have any auditory requirements? historical data will be lost with the manual migration process and vCOPs will see the vCenter Server appliance as a new vCenter Server environment. This manual process could be eased with the use of PowerCLI but unique to each environment. Using an existing vCenter Server database is not an option.
So there you have it, the vCenter Server appliance is fully capable however there are several key questions that will help you decide if it is the correct version for you. I have been a huge fan of the vCenter Server appliance since its introduction We want to hear from you the customers on what you are experiencing – when you decide to move to the appliance, do you regret it? were you successful? if you decided not to move to the appliance, which one of your criteria eliminated you? Please share your comments below.
