Dell 9.7(0.0) Plumbing Product User Manual


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when they restart. This option provides support for remote peers for their graceful restart without
supporting the feature itself.
You can implement BGP graceful restart either by neighbor or by BGP peer-group. For more information,
refer to the Dell Networking OS Command Line Interface Reference Guide.
Add graceful restart to a BGP neighbor or peer-group.
CONFIG-ROUTER-BGP mode
neighbor {ip-address | peer-group-name} graceful-restart
Set the maximum restart time for the neighbor or peer-group.
CONFIG-ROUTER-BGP mode
neighbor {ip-address | peer-group-name} graceful-restart [restart-time time-
in-seconds]
The default is 120 seconds.
Local router supports graceful restart for this neighbor or peer-group as a receiver only.
CONFIG-ROUTER-BGP mode
neighbor {ip-address | peer-group-name} graceful-restart [role receiver-only]
Set the maximum time to retain the restarting neighbor’s or peer-group’s stale paths.
CONFIG-ROUTER-BGP mode
neighbor {ip-address | peer-group-name} graceful-restart [stale-path-time
time-in-seconds]
The default is 360 seconds.
Filtering on an AS-Path Attribute
You can use the BGP attribute, AS_PATH, to manipulate routing policies.
The AS_PATH attribute contains a sequence of AS numbers representing the route’s path. As the route
traverses an AS, the ASN is prepended to the route. You can manipulate routes based on their AS_PATH
to affect interdomain routing. By identifying certain ASN in the AS_PATH, you can permit or deny routes
based on the number in its AS_PATH.
AS-PATH ACLs use regular expressions to search AS_PATH values. AS-PATH ACLs have an “implicit deny.”
This means that routes that do not meet a deny or match filter are dropped.
To configure an AS-PATH ACL to filter a specific AS_PATH value, use these commands in the following
sequence.
1. Assign a name to a AS-PATH ACL and enter AS-PATH ACL mode.
CONFIGURATION mode
ip as-path access-list as-path-name
2. Enter the parameter to match BGP AS-PATH for filtering.
CONFIG-AS-PATH mode
{deny | permit} filter parameter
Border Gateway Protocol IPv4 (BGPv4)
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