VMs configured with VMHA should be migrated to another storage and kept running when the primary storage is put on maintenance.

### The required feature described as a wish

When a primary storage is put on maintenance, the systemVMs are migrated to another primary storage and all user VMs are stopped. The user VMs are migrated on demand when they are manually started.

This might not be the intended behaviour for Instances on which VMHA is enabled and which are expected to by highly available. We might add a global config which will control if the Instances configured with VMHA are automatically migrated and are kept running.

Creating this issue to discuss and track this feature request.

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Discussed on https://github.com/apache/cloudstack/issues/12215
From the documentation https://docs.cloudstack.apache.org/en/4.22.0.0/adminguide/storage.html#maintenance-mode-for-primary-storage
`it will stop all guests that have any volume on that storage device.`

Iniziare dalla documentazione collegata sulla manutenzione dello storage primario e dall’issue #12215; il contenuto non indica file di implementazione né test. Chiarire la configurazione globale e il comportamento previsto per le istanze VMHA, inclusi la migrazione e il mantenimento delle VM in esecuzione, quindi definire test o documentazione che dimostrino il risultato concordato.

Scritto dal modello di indicizzazione a partire dal testo della issue.