I just checked some custom alarm available in latest vCenter & I do not see any alarm that we can set for DRS recommendation generated. However, I could find that custom alarm can be set for Storage DRS recommendation.
I will take this feature request forward as its one of important feature to be added.
Workaround can be :
1. It is better if you set DRS to "fully automated mode" & set Migration threshold to mid-point ie."Priority 3". 3 is recommended and most used migration threshold setting across enterprises.
Setting it too aggressive leads to more vMotion. Migration threshold can be set 1 through 5 . You can choose whichever suits you.
2.Manual check for recommendations. It is painful.
I will suggest you to read this white paper: It is must read :http://www.globalknowledge.nl/content/files/documents/White-Papers/virtualisatie-White-Paper-Ten-vSphere-HA-DRS
Thanks for the response vickyvision2020! I've seen the Storage DRS recommendation before but we're not currently using this feature as we do not have a Datastore cluster setup.
As for setting DRS for our current environment to fully automated. As I mentioned in my original post, this is a VDI environment and we sometimes have end users experience a slight VM "hang" or "freeze" when they are migrated to a different host. This is the reason for setting our migration automation level to manual. I don't want end users to be moved around automatically (even with a more conservative threshold) because of this experience. I suspect their might be something wrong with our vMotion configuration too because of this problem when migrating, but I'd rather leave DRS set to manual than risk having end users upset that their VM appeared to freeze for a moment (because DRS was automatically migrating it).
I have initiated communication with engineering team on DRS recommendation alarm.
I understand your concern. At the moment, monitoring DRS recommendations is the only option you have. However, even though if you keep it manual and there is considerable cluster imbalance, you have to apply the recommendations. I agree that in some cases, you can drop some of recommendations (ie. vMotion will be initiated). I suggest to keep migration threshold to mid-point (3) even though DRS is in Manual mode. It is better to resolve vMotion network issue.