VMFS UUID components

I thought this one is quite interesting to blog about. Obviously for VMware guru’s that just old common knowledge.

Let’s start with defining what’s is the UUID made up from:

The UUID is comprised of four components :

•  System Time
• CPU Timestamp
• Random Number
• MAC Address – Management Port uplink of the host used to resignature or create the datastore

Example:

~ # esxcfg-scsidevs -m

You can notice each datastore UUID ending with -00c2956461b as based on the management uplink:

The start of the UUID uses system time and CPU timestamp + random number to guarantee the uniqueness.