Brocade Multi-Service IronWare Routing Configuration Guide (Supporting R05.6.00) User Manual

Page 77

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Multi-Service IronWare Routing Configuration Guide

49

53-1003033-02

Configuring BGP4 neighbors

distribute-list in | out num,num,... specifies a distribute list to be applied to updates to or from the
specified neighbor. The in | out keywords specify whether the list is applied on updates received
from the neighbor, or sent to the neighbor. The num,num,... parameter specifies the list of
address-list filters. The device applies the filters in the order in which you list them and stops
applying the filters in the distribute list when a match is found.

To use an IP ACL instead of a distribute list, you can specify distribute-list acl-num in | out . In this
case, acl-num is an IP ACL.

NOTE

By default, if a route does not match any of the filters, the device denies the route. To change the
default behavior, configure the last filter as permit any any.

NOTE

The address filter must already be configured. Refer to

“Defining and applying IP prefix lists”

on

page 80.

ebgp-btsh enables GTSM protection for the specified neighbor. For details, see

“Generalized TTL

Security Mechanism support” on page 116

.

ebgp-multihop [num] specifies that the neighbor is more than one hop away and that the session
type with the neighbor is EBGP-multihop. This option is disabled by default. The num parameter
specifies the TTL you are adding for the neighbor. You can specify a number from 0 – 255. The
default is 0. If you leave the EBGP TTL value set to 0, the software uses the IP TTL value.

enforce-first-as ensures, for this neighbor, that the first AS listed in the AS_SEQUENCE field of an
AS path update message from EBGP neighbors is the AS of the neighbor that sent the update. For
details, refer to

“Requiring the first AS to be the neighbor AS”

on page 40.

filter-list in | out num,num,... specifies an AS-path filter list or a list of AS-path ACLs. The in | out
keywords specify whether the list is applied on updates received from the neighbor or sent to the
neighbor. If you specify in or out, The num,num,... parameter specifies the list of AS-path filters. The
device applies the filters in the order in which you list them and stops applying the filters in the
AS-path filter list when a match is found.

Alternatively, you can specify filter-list acl-num in | out | weight to use an AS-path ACL instead of an
AS-path filter list. In this case, acl-num is an AS-path ACL.

NOTE

By default, if an AS-path does not match any of the filters or ACLs, the device denies the route. To
change the default behavior, configure the last filter or ACL as permit any any.

NOTE

The AS-path filter or ACL must already be configured. Refer to

“Filtering AS-paths”

on page 76.

local-as as-num assigns a local AS number with the value specified by the as-num variable to the
neighbor being configured. The as-number has no default value. Its range is 1 – 4294967295.

NOTE

When the local-as option is used, the device automatically prepends the local AS number to the
routes that are received from the EBGP peer; to disable this behavior, include the no-prepend
keyword.

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