H3C Technologies H3C S12500 Series Switches - Manual (Page 168)

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Configuring IS-IS route redistribution
Redistributing large numbers of routes on a switch might affect the performance of other devices in the
network. In that case, you can configure a limit on the number of redistributed routes to limit the number
of routes to be advertised.
Only active routes can be redistributed. To verify route state, use the display ip routing-table protocol
command.
To configure IS-IS route redistribution from other routing protocols:
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. Redistribute routes
from another
routing protocol.
import-route protocol [ process-id |
all-processes | allow-ibgp ] [ cost cost |
cost-type { external | internal } | [ level-1 |
level-1-2 | level-2 ] | route-policy
route-policy-name | tag tag ] *
By default, no route is
redistributed.
By default, if no level is specified,
routes are redistributed into the
Level-2 routing table.
4. Configure the
maximum number
of redistributed
Level 1/Level 2
IPv4 routes.
import-route limit number Optional.
Configuring IS-IS route filtering
You can reference a configured ACL, IP prefix list, or routing policy to filter routes calculated from the
received LSPs and the routes redistributed from other routing protocols.
Filtering routes calculated from received LSPs
IS-IS saves the LSPs received from neighbors in the LSDB, uses the SPF algorithm to calculate the shortest
path tree with itself as the root, and installs the routes into the IS-IS routing table.
By reference a configured ACL, IP prefix list or routing policy, you can filter the calculated routes and only
the routes matching the filter can be added into the IS-IS routing table.
To filter routes calculated from received LSPs:
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. Filter routes calculated
from received LSPs.
filter-policy { acl-number | ip-prefix
ip-prefix-name | route-policy route-policy-name }
import
By default, no filtering is
configured.