Allied Telesis AT-S63 - Manual (Page 697)

AT-S63 Management Software Command Line Interface User’s Guide
Section IX: Management Security 697
The following command adds a TACACS+ server with an IP address
149.245.22.26 and specifies that this TACACS+ server is the third
TACACS+ server to be queried by the switch:
add tacacsserver ipaddress=149.245.22.26 order=3