Brocade Communications Systems ICX 7250 series, Руководство по настройке

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The ebgp, bgp, and multi-as parameters specify the change you are making to load sharing:
• ebgp - Multipath load sharing applies only to EBGP paths. Multipath load sharing is disabled for IBGP paths.
• ibgp - Multipath load sharing applies only to IBGP paths. Multipath load sharing is disabled for EBGP paths.
• multi-as - Multipath load sharing is enabled for paths from different autonomous systems.
By default, load sharing applies to EBGP and IBGP paths, and does not apply to paths from different neighboring autonomous systems.
Enhancements to BGP4 Multipath load sharing
Enhancements to BGP4 Multipath load sharing allows support for load sharing of BGP4 routes in IP ECMP even if the BGP4 Multipath
load sharing feature is not enabled through the
use-load-sharing option to the maximum-paths command. Using the following
commands, you can also set separate values for IBGP and EBGP multipath load sharing.
To set the number of equal-cost multipath IBGP routes or paths that will be selected, enter commands such as the following.
device(config)# router bgp
device(config-bgp)# maximum-paths ibgp
Syntax: [no] maximum-paths ibgp number
The number variable specifies the number of equal-cost multipath IBGP routes that will be selected. The range is 2 to 8. If the value is
set to 1, BGP4 level equal-cost multipath is disabled for IBGP routes.
To set the number of equal-cost multipath EBGP routes or paths that will be selected, enter commands such as the following.
device(config)# router bgp
device(config-bgp)# maximum-paths ebgp
Syntax: [no] maximum-paths ebgp num
The number variable specifies the number of equal-cost multipath EBGP routes that will be selected. The range is 2 to 8. If the value is
set to 1, BGP4 level equal-cost multipath is disabled for EBGP routes.
Specifying a list of networks to advertise
By default, the device sends BGP4 routes only for the networks you either identify with the network command or are redistributed into
BGP4 from OSPF, RIP, or connected routes.
NOTE
The exact route must exist in the IP route table before the device can create a local BGP4 route.
To configure the device to advertise network 10.157.22.0/24, enter the following command.
device(config-bgp-router)# network 10.157.22.0 255.255.255.0
Syntax: [no] network ip-addr ip-mask [ route-map map-name ] | [ weight num ] | [ backdoor ]
The ip-addr is the network number and the ip-mask specifies the network mask.
The route-map map-name parameter specifies the name of the route map you want to use to set or change BGP4 attributes for the
network you are advertising. The route map must already be configured. If it is not, the default action is to deny redistribution.
The weight num parameter specifies a weight to be added to routes to this network.
The backdoor parameter changes the administrative distance of the route to this network from the EBGP administrative distance (20 by
default) to the Local BGP4 weight (200 by default), tagging the route as a backdoor route. Use this parameter when you want the device
to prefer IGP routes such as RIP or OSPF routes over the EBGP route for the network.
Optional BGP4 configuration tasks
Brocade FastIron Layer 3 Routing Configuration Guide
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