VM-Aware

Here’s an interesting article about the performance overhead or ‘virtualisation tax’ as it is is so called of running a hypervisor.

In my opinion for most server workload types a 15%-20% overhead is more than acceptable when considering all the other benefits VMware brings with it.

VMotion, DRS, HA, speedy creation of new servers, simple and speedy cloning of existing servers for backup, testing and DR.  The list goes on.

I would say that maximising performance is important, but for most servers it is not the primary driver for most companies.

If you have a beast of an SQL Server, you don’t necessarily need to virtualise it.  This doesn’t mean that you should virtualise any application or web front-end servers that accompany it.

Firstly, let me start by saying that not everyone is going to want to ‘tweak’ with the bowels of RDP, but if you are so inclined then check out this article.

I stumbled upon it when wondering how I could get people to stop simply disconnecting sessions and logging off properly. (more…)

A few times over the years VMDK files have been ‘lost’ when a customer has had to shutown their storage in a less than graceful fashion.

In every case so far, touch wood, it is only the desciptor files that have been deleted so the raw data is still present in the *-flat.vmdk file.

It is actually quite simple to rescue the situation you simply restore from backup. Ahaha what if you do not have a backup, then there is another way. (more…)