Be Careful ! SSAS Analysis services cannot be uninstalled from a SQL cluster once installed

I was given the privilege of looking at SQL failover cluster installations across our support regions  to ensure that the clusters are built to the same standard and look as similar as possible. The idea is that since the cluster was for a consolidation project, and avoid the need to have satellite SQL installations all over the place, if a third party application which was based in London or same application based in New York, the database setup should be the same.

In this particular case, it wasn’t that straight forward as I wasn’t the one who installed the SQL cluster in the other region, I installed and configured the cluster for the region in which I work. Anyway, back to the main point now. I looked at the cluster in the other region and quickly noticed that SQL server analysis services aka SSAS was also installed on the same resource group as the SQL service. I recall reading the SQL 2008 R2 cluster setup best practices, and it was advised that SSAS should is best placed in its own resource group, and worst thing was that SSAS wasn’t actually required for what we wanted to achieve.

The plan was straightforward, well so I thought !! Whilst trying to remove/uninstall SSAS, it complained that the node would have to be evicted from the cluster, huuuuuuuuuuuuh.. Hang on, this isn’t what I wanted, I just wanted to remove a feature from the installation.

By the way I used the command line as follows.

1. setup.exe /ACTION=uninstall /FEATURES=AS /INSTANCENAME=<InstanceName>

 

It should be noted that this is only for a standalone installation and not for a clustered installation.

I raised a call with Microsoft support, and at first I was told that this is a bug, but later got told that this behaviour is actually by design but they have promised that their developers will work on a future release such that features can be uninstalled instead of having them coupled together.

 

http://support.microsoft.com/kb/2547273