vCenter Server – Appliance or Windows, which to deploy?

One of my New Years’ resolutions was to try and clear out the draft folder of my blog where I had started to write down my thoughts for different topics, only to get side-tracked…. Happens quite often as I’m the “Prince of Procrastination”…. =)

After deleting loads of draft posts which have become redundant due to product updates, I came across a topic that had been stewing for the past year! In fact the URL said “2013/11/04…..” O_o”

Having realised that there will be a big announcement on the 3rd Feb 2015 *cough* vSphere 6 *cough*, I thought that maybe I should get this post out before it becomes yet another redundant topic. =P
(BTW, I don’t believe vCSA will change much with vSphere 6 – just greater functionality and some other nice bits that I’m not allowed to talk about).

Ever since the vCenter Server Appliance was introduced with vSphere 5.0, customers have been asking me whether it’s a viable solution to deploy. Previously I have always said no, but when it was re-architected for vSphere 5.5, I have been encouraging all my customers to seriously consider the vCSA for any new deployments (or even upgrades).

In previous incarnations, vCSA did not scale well and you were pretty much limited to managing a maximum of 5 vSphere hosts and 50 VMs – this was mainly due to the limitations of the internal database. Exceeding these limits caused numerous problems, including, in one case, causing vCenter Server to stop responding!

With the launch of vCSA 5.5 VMware decided to re-engineer the appliance with an embedded vPostgres database that pushed the support up to 100 vSphere hosts and 3000 VMs. Add to that the integration with other VMware solutions (such as vCD, vCOPs, SRM, VUM, etc) and it now becomes viable for deployment in a Production environment…. especially since it’s so easy to install and you don’t have to faff around with Windows (which is always a bonus)!

  1. Ok, so let’s start with the obvious limitations – no SQL Server support for external database, no Linked Mode capability (which uses Microsoft ADAM) and limited support for IPv6. If you need either of these then it’s full-fat Windows deployment for you!
  2. If you don’t, then the next obvious question is what are your scalability requirements? vCSA supports up to 100 hosts and about 3,000 VMs with its internal DB. Attaching it to an Oracle DB scales you up to a maximum of 1,000 hosts and 10,000 VMs. So if you sit within those figures and don’t need to deploy a SQL server then great, let’s continue!
  3. Are you looking at upgrading an existing vCenter Server and do you want to keep its historical data? If you do, then unfortunately there’s no migration tool available to move from a Windows vCenter Server to the vCSA. =(
    It pretty much means you have to start from scratch with a fresh install of vCenter! You could probably use PowerCLI to script the migration of the data, but that would increase the complexity and time of your deployment – frankly not worth the effort!
    Also beware if you currently use distributed vSwitches as this will need to be re-configured as it’s stored within the vCenter Server DB!

So now that you’re good to deploy the vCSA, the obvious questions are:

  1. How good are you with Linux commands?
    • Whilst you no longer have to mess around with Windows, you now need to understand how to troubleshoot Linux… and it’s command line and not via a GUI (of sorts – there is a web admin page). It takes a while to work out how to start and stop services via CLI, but at least you can easily Google the problem and find a resolution quickly (or at least quicker than trying to Google Window error codes and messages!).
  2. Is there a requirement to keep the Linux appliance secure with patches and updates?
    • The vCSA is a SUSE Linux distribution, but one thing VMware does not do is publish regular updates for the Linux OS. It does however publish revisions to the appliance (update 2a at present) but only when there is a critical security requirement (such as last years’ OpenSSL vulnerability).
  3. How do you back it up?
    • Trying to backup the DB separately is quite fiddly and not recommended, and trying to install an agent for backup is the same….. the best way to backup the vCSA is using an image-based backup tool.

The obvious benefit is you no longer require a Windows license! I would love to say you could get rid of Windows and SQL server completely, but unfortunately if you wish to deploy VUM or SRM then you’ll still need to deploy them on a Windows OS with a SQL backend (hopefully future releases will address this reliance on Microsoft!).

In addition, the ease of deployment is phenomenally simple and wizard driven – so quite hard to go wrong. Plus you get the likes of Auto Deploy (disabled by default), Syslog & Dump Collector (enabled but not registered as a vCenter extension), plus Web Client and SSO installed automatically with the Appliance OVF.

The only minor point is the lack of vSphere CLI or PowerCLI…. If you wish to script then you’ll need to download the vSphere Management Assistant (vMA) Appliance.

So there you have it….. there’s no real reason why you shouldn’t be making your life easier by deploying the vCenter Server Appliance!!

Go ahead…. you know you want to! =)

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