Comment 1 for bug 1829852

I tried it at master (commit 6e4ab9714cc0ca147f61997aa7b68f88185ade5c).

The following message was shown.

stack@devstack-master:/opt/devstack$ nova-manage cell_v2 update_cell --cell_uuid b97750a1-6fee-4a8b-a675-f4b3184ade71 --transport-url rabbit://openstack:XXX@172.16.1.19:5672/
The specified transport_url and/or database_connection combination already exists for another cell with uuid 00000000-0000-0000-0000-000000000000.

But the transport url should be updated in this case.