How to prioritise datastores from which AppStacks are attached.

[Perttu]

Hi!

We're having the following problem: Our new cluster sees two different datastores, one vSAN and one LUN from FC fabric. The LUN datastore is shared between this cluster and few other independent hosts. Both of these datastores have up-to-date copies of AppStacks in cloudvolumes folder through a Storage Group replication. For some reason, App Volumes tends to favor this LUN over vSAN and thus AppStacks are assigned from it. However this LUN is much slower than the vSAN so we should get this other way round. I cannot set the LUN as not attachable without impairing App Volumes on other hosts.

We can solve this by creating new LUN which is not seen by vSAN cluster and let the other hosts use it but hey, are there any way to select which datastores should be preferred as primary and which as secondary?  This should be simple to achieve.

[Ray_handels · Accepted solution]

It depends on where your machines are stored.

If your machines are stored on the faster vSAN you can go into Configuration --> MAchine manager in the Appvolumes manager and then change the setting "Mount local copies of volumes".

What appvolumes does than is check if there is an appstack available on the datastore where the VDI resides on. If it can find the appstack there it will attach it from there.

For as far as I know you cannot set preferability based on performance in Appvolumes.

[Perttu]

Thank you. I think this resolves the issue for now. I had forgotten completely this feature.