+Ultra disks can't be used as OS disks, they can only be created as empty data disks. Ultra disks also can't be used with some features and functionality, including disk export, changing disk type, trusted launch, VM images, availability sets, or Azure disk encryption. The size of an Ultra Disk can't be expanded without either deallocating the VM or detaching the disk. Azure Backup and Azure Site Recovery do not support ultra disks. In addition, only un-cached reads and un-cached writes are supported. Snapshots for ultra disks are available but have additional limitations. See [Incremental snapshots of Premium SSD v2 and Ultra Disks](../articles/virtual-machines/disks-incremental-snapshots.md#incremental-snapshots-of-premium-ssd-v2-and-ultra-disks) for details.
0 commit comments