ECS4660-28F_Management Guide-R03

C HAPTER 51 | IP Routing Commands
Border Gateway Protocol (BGPv4)
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EXAMPLE
Console(config-router)#bgp bestpath compare-routerid
Console(config-router)#
bgp bestpath med This command enables comparison of the Multi Exit Discriminator (MED)
attribute for paths learned from confederation peers, and the treatment of
a route when the MED is missing. Use the no form to disable this feature.
SYNTAX
[no] bgp bestpath med {[confed] [missing-as-worst]}
confed – Compare MED in confederation path.
missing-as-worst – Consider as maximum MED value when
missing.
COMMAND MODE
Router Configuration
DEFAULT SETTING
When making the best-path selection, the router does not consider the
MED.
COMMAND USAGE
◆ The MED for paths learned from confederation peers is compared only if
no external autonomous systems (AS) appear in the path. If an
external AS is within the path, then the external MED is passed
transparently through the confederation, and it is not compared.
◆ If the missing-as-worst option is disabled, the missing MED is assigned
a value of 0, making a path missing the MED attribute the best path.
EXAMPLE
Console(config-router)#bgp bestpath med config missing-as-worst
Console(config-router)#
bgp default
local-preference
This command sets the default local preference used for best path selection
among local iBGP peers. Use the no form to restore the default setting.
SYNTAX
bgp default local-preference preference
preference – Degree of preference iBGP peers give local routes
during BGP best path selection. The higher the value, the more the
route is to be preferred. (Range: 0-4294967295)
COMMAND MODE
Router Configuration