How to register multiple Content Hosts with same UUID to Red Hat Satellite 6?

  Red Hat Satellite 6.5 and above.
  Red Hat Enterprise Linux with subscription-manager

  How can I register multiple machines which have the same UUID (BIOS/Motherboard ID) to Red Hat Satellite 6.5?
  The system properly registered and subscribe to Red Hat Satellite is not visible on the WebUI even after changing the context switch to any organization and any location.
  Experiencing following error while trying to register Content Hosts with the same UUID to Red Hat Satellite 6.5:

HTTP error (500 - Internal Server Error): Multiple profiles found. Consider removing XXX which match this host.

• A system's UUID is a motherboard product UUID, which is set by the hardware vendor and is encoded into the BIOS and should always be unique.

• However, if the hardware manufacturer for some reason has set the same UUID for multiple machines you will have to create a custom fact for every machine in order to register them as separate entities with Red Hat Satellite 6.5 or the Red Hat Customer Portal:

[root@client ~]# vi /etc/rhsm/facts/uuid.facts 
{"dmi.system.uuid": "customuuid"}

* customuuid = hostname which is unique for every machine.

• With Red Hat Satellite 6.6 the following works:

[root@client ~]# subscription-manager facts|grep dmi.system.uuid
dmi.system.uuid: 45AA7104-5CB0-4A75-945D-7173C8DC5783

Administer > Settings > Content(tab) > Host Duplicate DMI UUIDs - Add the UUID in the form of an array

- Reregister client machine. (Reregistering of both systems may be needed if the profile was unregistered by using the --force option)

- Verify that UUID in systems is different from the client machine:
Hosts -> All Hosts -> Client machine -> facts -> dmi -> systems

• If registering to the Red Hat Customer Portal, navigate to the Systems page and search for your new and old host after reregistering.

• The subscription-manager when trying to register a Content Host to Red Hat Satellite or Red Hat Customer Portal looks for dmi.system.uuid

parameter that should be unique.

• Creating a custom fact at /etc/rhsm/facts/ on the Content Host takes precedence over subscription-manager facts located in /var/lib/rhsm/facts/.

Check for duplicate resource errors like the one below in /var/log/foreman/production.log

2020-05-10T20:00:49 [E|kat|388f6507] POST: https://satellite.example.com/pulp/api/v2/consumers/: {"id":"ede5aaea-f460-48fb-aa2a-f8d49c7eb373","display_name":"client.example.com"}: {"content_type"=>"application/json", "accept"=>"application/json"}
409 Conflict: {"error": {"code": "PLP0018", "data": {"resource_id": "ede5aaea-f460-48fb-aa2a-f8d49c7eb373"}, "description": "Duplicate resource: ede5aaea-f460-48fb-aa2a-f8d49c7eb373", "sub_errors": []}, "http_request_method": "POST", "exception": null, "error_message": "Duplicate resource: ede5aaea-f460-48fb-aa2a-f8d49c7eb373", "_href": "/pulp/api/v2/consumers/", "http_status": 409, "resource_id": "ede5aaea-f460-48fb-aa2a-f8d49c7eb373", "traceback": null}

Check for duplicate RHSM facts between 2 hosts in /var/lib/rhsm/facts/facts.json:

{"dmi.system.uuid": "Not Present", "proc_cpuinfo.common.cpuid_level": "13", "virt.host_type": "kvm", "dmi.bios.address": "0xe8000", "lscpu.l1d_cache": "32K", "dmi.chassis.manufacturer": "QEMU", "distribution.name": "Red Hat Enterprise Linux Server", "lscpu.l1i_cache": "32K", "dmi.chassis.security_status": "Unknown", "dmi.memory.error_correction_type": "Multi-bit ECC", "dmi.processor.type": "Central Processor", 
--snip--
"dmi.memory.array_handle": "0x1000", "dmi.system.sku_number": "Not Specified", "dmi.processor.asset_tag": "Not Specified", "dmi.meta.cpu_socket_count": "8", "dmi.system.wake-up_type": "Power Switch"}