If an administrator does not enter the domain name when logging in to the device, the administrator is added to the global default administrative domain. If the system administrator has created a domain name for user authentication, for example, localuser, users must enter their user names with the domain name delimiter and domain name (@localuser). This reduces operation efficiency.
To facilitate operation, the system administrator can use the default-domain admin command to specify localuser as the name of the global default administrative domain. Then users do not need to enter @localuser when logging in.
<HUAWEI> system-view [HUAWEI] aaa [HUAWEI-aaa] domain localuser [*HUAWEI-aaa-domain-localuser] quit [*HUAWEI-aaa] default-domain admin localuser [*HUAWEI-aaa] commit
You can also find the answer in Common AAA Operations
