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Assigning a high priority to an is-is ip prefix, Setting the lsdb overload bit – H3C Technologies H3C SecPath F1000-E User Manual

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Step Command

Remarks

2.

Enter IS-IS view.

isis [ process-id ] [ vpn-instance
vpn-instance-name ]

N/A

3.

Configure the SPF
calculation interval.

timer spf maximum-interval [ initial-interval
[ second-wait-interval ] ]

Optional.
The default SPF calculation

interval is 10 seconds.

Assigning a high priority to an IS-IS IP prefix

An IS-IS topology change causes route convergence. By assigning a high priority to an IS-IS IP prefix, you

can achieve faster convergence for the specific routes.
To assign a high priority to an IS-IS IP prefix:

Step Command

Remarks

1.

Enter system view.

system-view

N/A

2.

Enter IS-IS view.

isis [ process-id ] [ vpn-instance
vpn-instance-name ]

N/A

3.

Assign a high priority to an

IS-IS IP prefix.

priority high { ip-prefix
prefix-name | tag tag-value }

Optional.
Not assigned by default.
If no IP prefix is assigned a high

priority, IS-IS host routes are
processed first in network

convergence because they have

higher priority than other types of
IS-IS routes.

Setting the LSDB overload bit

By setting the overload bit in sent LSPs, a router informs other routers of a failure that makes it incapable

of routing and forwarding packets.
When an IS-IS router cannot record the complete LSDB due to running out of memory or some other

reasons, it will calculate wrong routes. To make troubleshooting easier, you can temporarily isolate the

router from the IS-IS network by setting the overload bit.
To set the LSDB overload bit:

Step Command

Remarks

1.

Enter system view.

system-view

N/A

2.

Enter IS-IS view.

isis [ process-id ] [ vpn-instance vpn-instance-name ]

N/A

3.

Set the overload bit.

set-overload [ on-startup [ [ start-from-nbr system-id
[ timeout1 [ nbr-timeout ] ] ] | timeout2 ] [ allow { external
| interlevel } * ]

Not set by default.