Configuring is-is route filtering, Filtering routes calculated from received lsps, Filtering redistributed routes – H3C Technologies H3C SR8800 User Manual
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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.
If no level is specified, routes are
redistributed into the Level-2
routing table by default.
4.
Configure the
maximum number
of redistributed
Level 1/Level 2
IPv4 routes.
import-route limit number Optional.
NOTE:
Only active routes can be redistributed. Use the display ip routing-table protocol command to display
route state information.
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 referencing a configured ACL, IP prefix list or routing policy, you can filter the calculated routes. 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.
Filtering redistributed routes
IS-IS can redistribute routes from other routing protocols or other IS-IS processes, add them into the IS-IS
routing table and advertise them in LSPs.
By reference a configured ACL, IP prefix list or routing policy, you can filter redistributed routes and only
the routes matching the filter can be added into the IS-IS routing table and advertised to neighbors.
To configure the filtering of redistributed routes: