3Com 5500-EI PWR Reference Manual page 595

sending usernames to TACACS server. For this reason, the user-name-format command is
designed for you to specify whether or not ISP domain names are carried in the usernames to be
sent to TACACS server.
For a HWTACACS scheme, if you have specified to exclude ISP domain names from usernames,
you should not use this scheme in more than one ISP domain. Otherwise, such errors may occur:
the TACACS server regards two different users having the same name but belonging to different
ISP domains as the same user (because the usernames sent to it are the same).
Related commands: hwtacacs scheme.
Examples
# Specify to exclude ISP domain names from the usernames to be sent to TACACS server in
HWTACACS scheme hwt1.
<Sysname> system-view
System View: return to User View with Ctrl+Z.
[Sysname] hwtacacs scheme hwt1
[Sysname-hwtacacs-hwt1] user-name-format without-domain
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