I am trying to design a rightsizing strategy that works for my business. We currently have monthly maintenance windows of around 5 hours. We want to use the final hour of this window for any disruptive rightsizing that is required. To do this I have created custom groups based on our business services. These custom groups will have different maintenance windows so will require different policies. This is okay.
I also want non-disruptive resizing (will be resize up only) automated all the time. This is where it gets complicated.. If i assign a policy that enables non-disruptive mode, when the VMs hit the disruptive rightsizing scheduled window, the non-disruptive mode will overrule it (its the most conservative policy) and the actions will not be executed. Correct me if i'm wrong please?
To summarise, i want all my virtual machines to be able to resize up in a non-disruptive mode 99% of the time. The other 1% of the time i want the non-disruptive mode disabled and resize down automation scheduled to coincide with our agreed maintenance windows. This will therefore allow resize up to occur anytime without any server downtime, then resize down actions completed during the maintenance window when server downtime is okay. It also allows resize up in the maintenance windows for any servers where hot add is not enabled.
Lets say i have 3 groups of services called Service 1, Service 2 and Service 3. I want all 3 groups to resize up non-disruptively all the time (assuming hot add is enabled). Then i also want each group to be able to carry out any disruptive actions in a scheduled window. The scheduled window will be different for each group. What is the best strategy for this?
Hope this all makes sense, let me know if it doesn't.