Consistent SCSI target IDs across reboots
Linux SCSI target IDs change across reboots resulting in some really strange ordering of sda, sdb, sdc etc. Sometimes the ephemeral disk ends up on the end of the list, sometimes the data disk(s) go to the front. It's near impossible to import workloads into Azure with this device inconsistency.
This is not an Azure issue, but is fundamental to Linux. See https://www.usenix.org/legacy/publications/library/proceedings/bsdcon02/full_papers/kamp/kamp_html/index.html for a discussion.
referencing devices by uuid or using filesystem labels gets around this.