Procedure
Step 1
Run:
system-view
The system view is displayed.
Step 2
Run:
isis
[
process-id
]
The IS-IS view is displayed.
Step 3
Run:
filter-policy
{
acl-number
|
acl-name
acl-name
|
ip-prefix
ip-prefix-name
|
route-
policy
route-policy-name
}
import
Conditions for filtering IS-IS routes are configured.
----End
6.5.5 Configuring an Overload Bit for an IPv4 IS-IS Device
If an IS-IS device needs to be temporarily isolated, configure the IS-IS device to enter the
overload state to prevent other devices from forwarding traffic to this IS-IS device and prevent
blackhole routes.
Context
If an IS (for example, an IS to be upgraded or maintained) needs to be temporarily isolated,
configure the IS to enter the overload state so that no device will forward traffic to this IS.
IS-IS routes converge more quickly than BGP routes. To prevent blackhole routes on a network
where both IS-IS and BGP are configured, set an overload bit to instruct an IS to enter the
overload state during its start or restart. After BGP convergence is complete, cancel the overload
bit.
Procedure
Step 1
Run:
system-view
The system view is displayed.
Step 2
Run:
isis
[
process-id
]
The IS-IS view is displayed.
Step 3
Run:
set-overload
[
on-startup
[
timeout1
|
start-from-nbr
system-id
[
timeout1
[
timeout2
] ] |
wait-for-bgp
[
timeout1
] ] ] [
allow
{
interlevel
|
external
}
*
]
The overload bit is configured.
----End
S6700 Series Ethernet Switches
Configuration Guide - IP Routing
6 IS-IS Configuration
Issue 01 (2012-03-15)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
264
