для Cisco Cisco IOS Software Release 12.2(27)SBC
BGP Support for IP Prefix Import from Global Table into a VRF Table
Prerequisites for BGP Support for IP Prefix Import from Global Table into a VRF Table
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Cisco IOS Release: Multiple releases (see the Feature History table)
Prerequisites for
BGP Support for IP Prefix Import from
Global Table into a VRF Table
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Border Gateway Protocol peering sessions are established.
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CEF or dCEF (for distributed platforms) is enabled on all participating routers.
Restrictions for
BGP Support for IP Prefix Import from Global
Table into a VRF Table
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Only IPv4 unicast and multicast prefixes can be imported to a VRF with this feature.
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A maximum of 5 VRF instances per router can be created to import IPv4 prefixes from the global
routing table.
routing table.
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IPv4 prefixes imported into a VRF, using this feature, cannot be imported into a VPNv4 VRF.
Information About
BGP Support for IP Prefix Import from
Global Table into a VRF Table
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Importing IPv4 Prefixes into a VRF
The BGP Support for IP Prefix Import from Global Table into a VRF Table feature introduces the
capability to import IPv4 unicast prefixes from the global routing table into a Virtual Private Network
(VPN) routing/forwarding instance (VRF) table using an import map. This feature extends the
functionality of VRF import-map configuration to allow IPv4 prefixes to be imported into a VRF based
on a standard community. Both IPv4 unicast and multicast prefixes are supported. No Multiprotocol
Label Switching (MPLS) or route target (import/export) configuration is required.
capability to import IPv4 unicast prefixes from the global routing table into a Virtual Private Network
(VPN) routing/forwarding instance (VRF) table using an import map. This feature extends the
functionality of VRF import-map configuration to allow IPv4 prefixes to be imported into a VRF based
on a standard community. Both IPv4 unicast and multicast prefixes are supported. No Multiprotocol
Label Switching (MPLS) or route target (import/export) configuration is required.
IP prefixes are defined as match criteria for the import map through standard Cisco IOS filtering
mechanisms. For example, an IP access-list, an IP prefix-list, or an IP as-path filter is created to define
an IP prefix or IP prefix range, and then the prefix or prefixes are processed through a match clause in a
route map. Prefixes that pass through the route map are imported into the specified VRF per the import
map configuration.
mechanisms. For example, an IP access-list, an IP prefix-list, or an IP as-path filter is created to define
an IP prefix or IP prefix range, and then the prefix or prefixes are processed through a match clause in a
route map. Prefixes that pass through the route map are imported into the specified VRF per the import
map configuration.