Riverbed SteelHead 3070-SD, Руководство пользователя

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Configuring BGP and OSPF Routing Policies on SteelHead SD | 71
What are routing policies?
• Static and connected route injection BGP.
• OSPF route injection in BGP.
• Policies at the BGP neighbor level.
• Default route origination in BGP for a neighbor.
Each route map clause has two types of values:
• A match value selects routes to which the clause should be applied.
• A set value modifies information that will be redistributed into the target protocol.
For each route that is being redistributed, the router evaluates the match criteria of a clause in the route
map. If the match criteria succeed, then the route is redistributed and some of the attributes may be
modified by the set clause. If the route doesn’t match any clause in a route map, then the route
redistribution is denied.
Once configured, the route-maps can be applied to satisfy the needs of these use-cases:
• Route Injection in OSPF - OSPF redistributes static, connected, and BGP routes. This route-map
category contains only a match criteria. The route map depends on the following objects:
– IP prefix lists
– Interface (all zones/uplinks associated with SteelHead SD appliances in the given organization)
• Default Route Origination in OSPF - Redistributes the default route in OSPF. This category of route-
map contains both match and set criteria. This is the simplest route-map category that is not
dependent on other objects.
• Static and Connected Route Injection in BGP - Redistributes static and connected routes in BGP
using a list of IPv4 prefixes. This route-map category contains both match and set criteria. Also
dependent on the following objects:
– IPv4 prefix lists
– Interface
• OSPF Route Injection in BGP - Redistributes OSPF routes in BGP using a list of IPv4 prefixes. This
category of route map contains both match and set criteria.
• Policies at the BGP Neighbor Level - Redistributes routes for BGP neighbors using a community list
and list of IP next-hop prefixes. You can set the origin-type attribute in this use case to influence
path selection based on the origin of a prefix. This route-map category contains both match and set
criteria. The match criteria in this use case is dependent on:
– Community list
– Prefix list
• Default Route Origination in BGP for a Neighbor -Redistributes the route in BGP. This route-map
category contains both match and set criteria. There are not any dependent objects for this type of
route map.
• User Defined Route Map - Enables you to create route map that includes all the match and set
criteria available.