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The set protocols bgp ipv4-unicast aggregate-address as-set command creates an aggregate address entry in IPv4 format in the BGP routing table. The AS_PATH attribute advertised for this route will contain an AS_SET consisting of all AS numbers contained in all paths that are being summarized.
The delete protocols bgp ipv4-unicast aggregate-address as-set command removes the specified aggregate address entry.
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set protocols bgp [vrf <vrf-name>] ipv4-unicast aggregate-address <ipv4/prefixlen> [as-set]
delete protocols bgp [vrf <vrf-name>] ipv4-unicast aggregate-address <ipv4/prefixlen> [as-set]
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