HPE FlexNetwork 5510 HI Series Layer 3 - Ip Routing Configuration Guide

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To configure route summarization on an ASBR:
Step Command Remarks
1. Enter system view.
system-view
N/A
2. Enter OSPF view.
ospf
[ process-id |
router-id
router-id
|
vpn-instance
vpn-instance-name ]*
N/A
3. Configure ASBR route
summarization.
asbr-summary
ip-address
{ mask-length | mask } [
cost
cost |
not-advertise
|
nssa-only
|
tag
tag ]
*
By default, route summarization is
not configured on an ASBR.
Configuring discard routes for summary networks
Discard routes help prevent routing black holes when route summarization is configured on ABRs
and ASBRs.
During route summarization, an ABR or ASBR generates a discard route for the summary network.
The destination and output interface of the discard route is the summary network and interface Null 0.
When receiving packets destined for a nonexistent network that is a part of the summary network,
the ABR or ASBR discards the packets according to the discard route.
For example, Router A summarizes networks 19.1.1.0/24, 19.1.2.0/24, and 19.1.3.0/24 into network
19.1.0.0/16, and advertises the summary network to Router B. When Router B receives a packet
destined for 19.1.4.0/24, Router B forwards the packet to Router A according to the summary route.
Because no specific route to 19.1.4.0/24 exists, Router A discards the packet according to the
discard route.
To configure discard routes for summary networks:
Step Command Remarks
1. Enter system view.
system-view
N/A
2. Enter OSPF view.
ospf
[ process-id |
router-id
router-id |
vpn-instance
vpn-instance-name ] *
N/A
3. Configure discard routes
for summary networks.
discard-route
{
external
{ external-preference |
suppression
} |
internal
{ internal-preference |
suppression
} }
*
By default:
• The ABR or ASBR generates
discard routes for summary
networks.
• The preference of discard
routes is 255.
Configuring received OSPF route filtering
Perform this task to filter routes calculated using received LSAs.
The following filtering methods are available:
• Use an ACL or IP prefix list to filter routing information by destination address.
• Use the gateway keyword to filter routing information by next hop.
• Use an ACL or IP prefix list to filter routing information by destination address and at the same
time use the gateway keyword to filter routing information by next hop.
• Use a routing policy to filter routing information.
To configure OSPF to filter routes calculated using received LSAs:

HPE FlexNetwork 5510 HI Series Specifications

General

Brand	HPE
Model	FlexNetwork 5510 HI Series
Category	Switch
Language	English