The following is listed in the help page on the command line:

Usage: ./ovm_admin [options]

Options:
--help: Shows this message
--createuser: Create new Oracle VM Manager admin user
--deleteuser: <admin> Delete Oracle VM Manager admin user
--listusers: List Oracle VM Manager users
--modifyuser: Modify Oracle VM Manager user password
--lockusers: <tries> Max login tries before locking account. This setting is global.
--unlockuser: <admin> Unlock user account
--modifyds <SID> <host> <port> [<type>] Modify Data Store 'OVMDS'. Options of <type>: 
              oracle, mysql
--listconfig: List configuration
--rotatelogsdaily: <time> Rotate Logs Daily (HH:MM)
--rotatelogsbysize: <size> Rotate Logs By Size (KB)