3Com MSR 50 Series Configuration Manual page 903

The authentication configured on an interface applies to the hello packet in order
to authenticate neighbors. All interfaces within a network must share the same
authentication password at the same level.
Follow these steps to configure the authentication function:
n
The level-1 and level-2 keywords in the isis authentication-mode command
are only supported on the Ethernet or GigabitEthernet interface of a router and
the interface must be configured with the isis enable command first.
Configuring LSDB When the overload tag is set on a router, other routers will not send packets to the
Overload Tag router except for the packets destined to the network directly connected to the
router.
The overload tag can be used for troubleshooting as well. You can temporarily
isolate a router from the IS-IS network by setting the overload tag.
Follow these steps to configure the LSDB overload tag:
To do...
Enter system view
Enter IS-IS view
Specify the area
authentication mode
Specify the routing domain
authentication mode
Return to system view
Enter interface view
Specify the authentication
mode and password
To do... Use the command...
Enter system view system-view
Enter IS-IS view isis [ process-id ] [ vpn-instance
vpn-instance-name ]
Configure the overload set-overload [ on-startup
tag start-from-nbr system-id [ timeout
[ nbr-timeout ] ] ] [ allow { interlevel |
external } * ]
Tuning and Optimizing IS-IS Network
Use the command...
system-view
isis [ process-id ]
[ vpn-instance
vpn-instance-name ]
area-authentication-mode
{ simple | md5 } password
[ ip | osi ]
domain-authentication-mo
de { simple | md5 } password
[ ip | osi ]
quit
interface interface-type
interface-number
isis authentication-mode
{ simple | md5 } password
[ level-1 | level-2 ] [ ip | osi ]
903
Remarks
--
--
Required
No authentication is enabled
for Level-1 routing
information, and no password
is specified by default.
Required
No authentication is enabled
for Level-2 routing
information, and no password
is specified by default.
--
--
Optional
No authentication and
password are available by
default.
Remarks
--
--
Required
Not configured by
default