RHEL / CentOS - UUIDs differ between VMware and OS

Recently, some un-explanatory behavior with VMware and CentOS / RHEL has caught my attention because the virt-who entitlement kept failing due to different UUIDs reported by vCenter and 'dmidecode' / 'subscription-manager facts' (VMware KB Article).

To give you an example:

 Hardware Version: 13 (ESXi 6.5)  
 vCenter UUID: 4230a396-6b9c-8a0b-7502-f63969069208  
 Host Facts UUID:  
 - dmidecode UUID: 96a33042-9c6b-0b8a-7502-f63969069208  
 - dmi.system.uuid: 96A33042-9C6B-0B8A-7502-F63969069208  
 - virt.uuid: 96A33042-9C6B-0B8A-7502-F63969069208

As you can see, the UUIDs from vCenter and dmidecode / subscription-manager facts do not match up due to a change in endianness. The profiles that happened to show this behavior are

Hardware Version 13 (ESXi 6.5 (vmx-13))
Hardware Version 14 (ESXi 6.7 (vmx-14))
Hardware Version 15 (ESXI 6.7u2 (vmx-15))

However, with version 'Hardware Version 11 (vmx-11) everything seems to work fine. Keep this in mind for a possible workaround.

 Hardware Version: 11 (ESXi 6.0)  
 vCenter UUID: 4230142d-e6c5-9267-7051-3eba693ae7b1  
 Host Facts UUID:  
 - dmidecode UUID: 4230142d-e6c5-9267-7051-3eba693ae7b1  
 - dmi.system.uuid: 4230142d-e6c5-9267-7051-3eba693ae7b1  
 - virt.uuid: 4230142d-e6c5-9267-7051-3eba693ae7b1

If you are using RHEL and subscribe the hosts to a satellite / foreman(katello) host, you could just query the API and re-register the host based on the entitlement-state.

Feel free to comment and / or suggest a topic.

Comments

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