ostree-admin-set-origin man page

ostree admin set-origin {REMOTENAME} {URL} [BRANCH]

Add a new remote named REMOTENAME (if it does not already exist). Then change the origin file for the current deployment. This is the ref that will be "tracked" and upgraded with ostree admin upgrade.

--set=KEY=VALUE

Set an option for the remote.

--index=INDEX

Change the origin of the deployment numbered INDEX (starting from 0).

$ ostree admin set-origin exampleos http://os.example.com/repo exampleos/10.0/master/router