Extreme Networks ExtremeWare XOS 11.3, Руководство пользователя

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Border Gateway Protocol
ExtremeWare XOS 11.3 Concepts Guide
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Exporting routes from OSPF to BGP and from BGP to OSPF are discrete configuration functions. To run
OSPF and BGP simultaneously, you must first configure both protocols and then verify the independent
operation of each. Then you can configure the routes to export from OSPF to BGP and the routes to
export from BGP to OSPF.
Configuring Route Redistribution
Exporting routes between any two routing protocols are discrete configuration functions. For example,
you must configure the switch to export routes from OSPF to BGP; and, if desired, you must configure
the switch to export routes from BGP to OSPF. You must first configure both protocols and then verify
the independent operation of each. Then you can configure the routes to export from OSPF to BGP and
the routes to export from BGP to OSPF.
You can use route maps to associate BGP attributes including Community, NextHop, MED, Origin, and
Local Preference with the routes. Route maps can also be used to filter out exported routes.
To enable or disable the exporting of OSPF, RIP, static, and direct (interface) routes to BGP, use the
following commands:
enable bgp export [direct | ospf | ospf-extern1 | ospf-extern2 | ospf-inter | ospf-
intra | rip | static] {address-family [ipv4-unicast | ipv4-multicast]} {export-policy
<policy-name>}
disable bgp export [direct | ospf | ospf-extern1 | ospf-extern2 | ospf-inter | ospf-
intra | rip | static] {address-family [ipv4-unicast | ipv4-multicast]}
Using the
export
command to redistribute routes complements the redistribution of routes using the
configure bgp add network
command. The
configure bgp add network
command adds the route
to BGP only if the route is present in the routing table. The
enable bgp export
command redistributes
the specified routes from the routing table to BGP. If you use both commands to redistribute routes, the
routes redistributed using the
network
command take precedence over routes redistributed using the
export
command.
BGP Static Network
ExtremeWare XOS BGP allows users to add static networks in BGP, which will be redistributed
(advertised) into the BGP domain if there is a corresponding active route in the IP routing table. Users
can associate a policy with the static BGP network to change or to set the route attributes before the
route is advertised to the BGP neighbors.
Use the following command to create a static BGP network:
configure bgp add network {address-family [ipv4-unicast | ipv4-multicast]} <ipaddr>/
<mask_len> {network-policy <policy>}
Use the following command to delete a static BGP network
configure bgp delete network {address-family [ipv4-unicast | ipv4-multicast]} [all |
<ipaddress/mask length>]