{"id":4309,"date":"2026-06-01T09:00:00","date_gmt":"2026-06-01T00:00:00","guid":{"rendered":"http:\/\/daimaru-tech-blog.com\/?p=4309"},"modified":"2026-04-02T09:27:28","modified_gmt":"2026-04-02T00:27:28","slug":"%e3%80%90bgp%e5%85%a5%e9%96%80%e3%80%91bgp-attribute%ef%bc%88%e5%b1%9e%e6%80%a7%ef%bc%89%e3%81%aemed%e3%81%ab%e3%81%a4%e3%81%84%e3%81%a6","status":"publish","type":"post","link":"https:\/\/daimaru-tech-blog.com\/?p=4309","title":{"rendered":"\u3010BGP\u5165\u9580\u3011BGP Attribute\uff08\u5c5e\u6027\uff09\u306eMED\u306b\u3064\u3044\u3066"},"content":{"rendered":"\n

\u306f\u3058\u3081\u306b<\/h2>\n\n\n\n

\u3053\u3093\u306b\u3061\u306f\u3002\u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u30a8\u30f3\u30b8\u30cb\u30a2\u306e\u300c\u3060\u3044\u307e\u308b\u300d<\/span><\/span><\/strong>\u3067\u3059\u3002<\/p>\n\n\n\n

\u4eca\u56de\u306f\u3001BGP Attirbute\uff08\u5c5e\u6027\uff09\u30b7\u30ea\u30fc\u30ba\u3068\u3057\u3066\u3001\u300cMED\u300d\u306b\u3064\u3044\u3066\u307e\u3068\u3081\u3066\u3044\u304d\u305f\u3044\u3068\u601d\u3044\u307e\u3059\u3002<\/p>\n\n\n

\n
\n
\n
\n \n <\/div>\n
\n
\u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u30a8\u30f3\u30b8\u30cb\u30a2\u306e\u6559\u79d1\u66f8<\/div>\n
\u301c\u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u30a8\u30f3\u30b8\u30cb\u30a2\u3092\u76ee\u6307\u3059\u4eba\u3001\u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u30a8\u30f3\u30b8\u30cb\u30a2\u306b\u306a\u3063\u305f\u3070\u304b\u308a\u306e\u4eba\u306b\u304a\u3059\u3059\u3081\u306e1\u518a\u301c<\/div>\n
\n \n Amazon\u3067\u898b\u308b\n <\/a>\n \n \u697d\u5929\u3067\u898b\u308b\n <\/a>\n <\/div>\n <\/div>\n <\/div>\n<\/center>\n<\/div>\n\n\n

MED\u3068\u306f\uff1f<\/h2>\n\n\n\n

\u6982\u8981<\/h3>\n\n\n\n

BGP\u306eAttribute\uff08\u5c5e\u6027\uff09\u306e1\u3064\u3067\u3042\u308b\u300cMED<\/strong>\u300d\u306f\u3001\u5185\u90e8\u304b\u3089\u5916\u90e8AS\u3078\u306e\u7d4c\u8def\uff08\u30a4\u30f3\u30bf\u30fc\u30cd\u30c3\u30c8\u304b\u3089\u5185\u90e8\u3078\u306e\u30c8\u30e9\u30d5\u30a3\u30c3\u30af\uff09\u3092\u5236\u5fa1\u3059\u308b\u3053\u3068\u3092\u30e1\u30a4\u30f3\u306b\u5229\u7528<\/strong>\u3055\u308c\u3066\u3044\u307e\u3059\u3002<\/p>\n\n\n\n

MED\u306f\u3001\u30c7\u30d5\u30a9\u30eb\u30c8\u5024\u304c\u300c0\u300d\u3067\u3042\u308a\u3001\u5024\u304c\u5c0f\u3055\u3044\u307b\u3069\u512a\u5148\u5ea6\u304c\u9ad8\u304f<\/span>\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n

\n
AS100<\/b><\/font><\/div><\/div><\/div><\/foreignObject>AS100<\/text><\/switch><\/g>
AS200<\/b><\/font><\/div><\/div><\/div><\/foreignObject>AS200<\/text><\/switch><\/g>
AS300<\/b><\/font><\/div><\/div><\/div><\/foreignObject>AS300<\/text><\/switch><\/g>
AS400<\/b><\/font><\/div><\/div><\/div><\/foreignObject>AS400<\/text><\/switch><\/g>
10.0.1.1\u5411\u3051\u306eMED 300<\/div><\/div><\/div><\/foreignObject>10.0.1.1\u5411\u3051\u306eMED 300<\/text><\/switch><\/g>
Lo0: 10.0.4.1<\/font><\/div><\/div><\/div><\/foreignObject>Lo0: 10.0.4.1<\/text><\/switch><\/g>
10.0.1.1\u5411\u3051\u306eMED 100<\/div><\/div><\/div><\/foreignObject>10.0.1.1\u5411\u3051\u306eMED 100<\/text><\/switch><\/g>
MED\u5024\u304c\u5c0f\u3055\u3044\u65b9\u304c\u30d9\u30b9\u30c8\u30d1\u30b9<\/div><\/div><\/div><\/foreignObject>MED\u5024\u304c\u5c0f\u3055\u3044\u65b9\u304c\u30d9\u30b9\u30c8\u30d1\u30b9<\/text><\/switch><\/g>
\u30d9\u30b9\u30c8\u30d1\u30b9<\/b><\/font><\/div><\/div><\/div><\/foreignObject>\u30d9\u30b9\u30c8\u30d1\u30b9<\/text><\/switch><\/g>
AS500<\/b><\/font><\/div><\/div><\/div><\/foreignObject>AS500<\/text><\/switch><\/g>
Lo0: 10.0.1.1<\/font><\/div><\/div><\/div><\/foreignObject>Lo0: 10.0.1.1<\/text><\/switch><\/g><\/g>Text is not SVG – cannot display<\/text><\/a><\/switch><\/svg><\/center>\n<\/div><\/div>\n\n\n
\n
\n
\n
\n \n <\/div>\n
\n
\u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u30b9\u30da\u30b7\u30e3\u30ea\u30b9\u30c82026\u5e74\u7248<\/div>\n
\u301c\u5408\u683c\u306e\u305f\u3081\u306e\u77e5\u8b58\u30fb\u89e3\u304d\u65b9\u3092\u8a73\u3057\u304f\u89e3\u8aac\u3057\u305f\u300c\u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u30b9\u30da\u30b7\u30e3\u30ea\u30b9\u30c8\u8a66\u9a13\u300d\u306e\u6c7a\u5b9a\u7248\u5b66\u7fd2\u66f8\uff01\u301c<\/div>\n
\n \n Amazon\u3067\u898b\u308b\n <\/a>\n\n <\/div>\n <\/div>\n <\/div>\n<\/center>\n<\/div>\n\n\n

\u8a2d\u5b9a\u65b9\u6cd5\uff08Cisco IOS\uff09<\/h3>\n\n\n\n

MED\u3092\u5909\u66f4\u3059\u308b\u305f\u3081\u306b\u306f\u3001\u4ed6\u306eAttirbute\uff08\u5c5e\u6027\uff09\u3068\u540c\u69d8\u306b\u300cPrefix-List\u300d\u3001\u300cRoute-Map\u300d\u3092\u5229\u7528\u3057\u307e\u3059\u3002<\/p>\n\n\n\n

#prefix-list\u306e\u5b9a\u7fa9\nip prefix-list <\/span><\u30ea\u30b9\u30c8\u540d><\/span> permit <\/span><IP Range>\/<prefix><\/span>\n\n<\/span>#route-map\u306e\u5b9a\u7fa9\nroute-map<\/span> <\u30de\u30c3\u30d7\u540d><\/span> permit 10\n match ip address prefix-list <\/span><\u30ea\u30b9\u30c8\u540d><\/span>\n set metric <\/span><\u30e1\u30c8\u30ea\u30c3\u30af\u5024><\/span>\n<\/span>\n\n<\/span>#BGP\u3078\u306e\u8a2d\u5b9a\u9069\u7528\nrouter bgp <\/span><AS\u756a\u53f7><\/span>\n neighbor <\/span><Neighbor\u306eIP\u30a2\u30c9\u30ec\u30b9><\/span> route-map <\/span><\u30de\u30c3\u30d7\u540d><\/span> [in|out]<\/span><\/code><\/pre>\n\n\n
\n
\n    
\n        
\n            \n        <\/div>\n        
\n            
\u30a4\u30f3\u30bf\u30fc\u30cd\u30c3\u30c8\u30eb\u30fc\u30c6\u30a3\u30f3\u30b0\u5165\u9580 \u7b2c3\u7248<\/div>\n            
\u301c\u56f3\u89e3\u3067\u308f\u304b\u308b\u7d4c\u8def\u5236\u5fa1\u306e\u4ed5\u7d44\u307f!\u301c<\/div>\n            
            \n                \n                    Amazon\u3067\u898b\u308b\n                <\/a>\n                 \n                    \u697d\u5929\u3067\u898b\u308b\n                <\/a>\n\n            <\/div>\n        <\/div>\n    <\/div>\n<\/center>\n<\/div>\n\n\n
\u52d5\u4f5c\u78ba\u8a8d<\/h3>\n\n\n\n
\u691c\u8a3c\u69cb\u6210<\/h4>\n\n\n\n
\u691c\u8a3c\u69cb\u6210\u306f\u4ed6\u306eAttribute\uff08\u5c5e\u6027\uff09\u3068\u540c\u69d8\u306e\u69cb\u6210\u306b\u3059\u308b\u4e88\u5b9a\u3067\u3059\u3002<\/p>\n\n\n\n
\n
AS100<\/b><\/font><\/div><\/div><\/div><\/foreignObject>AS100<\/text><\/switch><\/g>
AS200<\/b><\/font><\/div><\/div><\/div><\/foreignObject>AS200<\/text><\/switch><\/g>
\u30eb\u30fc\u30bf1<\/b><\/font><\/div><\/div><\/div><\/foreignObject>\u30eb\u30fc\u30bf1<\/text><\/switch><\/g>
\u30eb\u30fc\u30bf2<\/b><\/font><\/div><\/div><\/div><\/foreignObject>\u30eb\u30fc\u30bf2<\/text><\/switch><\/g>
\u30eb\u30fc\u30bf3<\/b><\/font><\/div><\/div><\/div><\/foreignObject>\u30eb\u30fc\u30bf3<\/text><\/switch><\/g>
\u30eb\u30fc\u30bf4<\/b><\/font><\/div><\/div><\/div><\/foreignObject>\u30eb\u30fc\u30bf4<\/text><\/switch><\/g>
\u30eb\u30fc\u30bf5<\/b><\/font><\/div><\/div><\/div><\/foreignObject>\u30eb\u30fc\u30bf5<\/text><\/switch><\/g>
\u30eb\u30fc\u30bf6<\/b><\/font><\/div><\/div><\/div><\/foreignObject>\u30eb\u30fc\u30bf6<\/text><\/switch><\/g>
\u30eb\u30fc\u30bf7<\/b><\/font><\/div><\/div><\/div><\/foreignObject>\u30eb\u30fc\u30bf7<\/text><\/switch><\/g>
192.168.1.0\/30<\/div><\/div><\/div><\/foreignObject>192.168…<\/text><\/switch><\/g>
192.168.2.0\/30<\/div><\/div><\/div><\/foreignObject>192.168…<\/text><\/switch><\/g>
10.1.0.0\/30<\/div><\/div><\/div><\/foreignObject>10.1.0….<\/text><\/switch><\/g>
10.2.0.0\/30<\/div><\/div><\/div><\/foreignObject>10.2.0….<\/text><\/switch><\/g>
10.2.1.0\/30<\/div><\/div><\/div><\/foreignObject>10.2.1….<\/text><\/switch><\/g>
10.2.2.0\/30<\/div><\/div><\/div><\/foreignObject>10.2.2….<\/text><\/switch><\/g>
10.1.1.0\/30<\/div><\/div><\/div><\/foreignObject>10.1.1….<\/text><\/switch><\/g>
10.1.2.0\/30<\/div><\/div><\/div><\/foreignObject>10.1.2….<\/text><\/switch><\/g>
10.1.3.0\/30<\/div><\/div><\/div><\/foreignObject>10.1.3….<\/text><\/switch><\/g>
Lo0:10.10.X.1\/32<\/div><\/div><\/div><\/foreignObject>Lo0:10….<\/text><\/switch><\/g>
Lo0:10.20.X.1\/32<\/div><\/div><\/div><\/foreignObject>Lo0:10….<\/text><\/switch><\/g>
AS300<\/b><\/font><\/div><\/div><\/div><\/foreignObject>AS300<\/text><\/switch><\/g>
\u30eb\u30fc\u30bf8<\/b><\/font><\/div><\/div><\/div><\/foreignObject>\u30eb\u30fc\u30bf8<\/text><\/switch><\/g>
192.168.3.0\/30<\/div><\/div><\/div><\/foreignObject>192.168…<\/text><\/switch><\/g>
192.168.4.0\/30<\/div><\/div><\/div><\/foreignObject>192.168…<\/text><\/switch><\/g>
AS400<\/b><\/font><\/div><\/div><\/div><\/foreignObject>AS400<\/text><\/switch><\/g>
192.168.5.0\/30<\/div><\/div><\/div><\/foreignObject>192.168…<\/text><\/switch><\/g>
192.168.6.0\/30<\/div><\/div><\/div><\/foreignObject>192.168…<\/text><\/switch><\/g>
Lo0:10.30.X.1\/32<\/div><\/div><\/div><\/foreignObject>Lo0:10.30.X.1\/32<\/text><\/switch><\/g>
Lo0:10.40.X.1\/32<\/div><\/div><\/div><\/foreignObject>Lo0:10….<\/text><\/switch><\/g>
\u30eb\u30fc\u30bf9<\/b><\/font><\/div><\/div><\/div><\/foreignObject>\u30eb\u30fc\u30bf9<\/text><\/switch><\/g><\/g>Text is not SVG – cannot display<\/text><\/a><\/switch><\/svg><\/center>\n<\/div><\/div>\n\n\n\n
\u4e8b\u524d\u78ba\u8a8d\uff08Rourer3\uff09<\/h4>\n\n\n\n
Router7\u304c\u6240\u6301\u3059\u308b\u300c10.20.7.1\/32\u300d\u5411\u3051\u306eMED\u5024\u3092\u78ba\u8a8d\u3057\u3066\u3044\u304d\u307e\u3059\u3002<\/p>\n\n\n\n
Router3 BGP\u30c6\u30fc\u30d6\u30eb<\/span><\/div>
\n
Router3#show ip bgp<\/span>\nBGP table version is 13, local router ID is 10.10.3.1\nStatus codes: s suppressed, d damped, h history, * valid, > best, i - internal,\n              r RIB-failure, S Stale, m multipath, b backup-path, f RT-Filter,\n              x best-external, a additional-path, c RIB-compressed,\n              t secondary path,\nOrigin codes: i - IGP, e - EGP, ? - incomplete\nRPKI validation codes: V valid, I invalid, N Not found\n\n     Network          Next Hop            Metric LocPrf Weight Path\n r>i  10.10.1.1\/32     10.10.1.1                0    100      0 i\n r>i  10.10.2.1\/32     10.10.2.1                0    100      0 i\n *>   10.10.3.1\/32     0.0.0.0                  0         32768 i\n r>i  10.10.4.1\/32     10.10.4.1                0    100      0 i\n * i  10.20.5.1\/32     10.10.2.1                0    100      0 200 i\n *>i                   10.10.1.1                0    100      0 200 i\n *>i  10.20.6.1\/32     10.10.1.1                0    100      0 200 i\n * i                   10.10.2.1                0    100      0 200 i\n *>i  10.20.7.1\/32     10.10.1.1                0    100      0 200 i\n * i                   10.10.2.1                0    100      0 200 i<\/span>\n *>i  10.30.8.1\/32     10.10.2.1              400    100      0 300 i\n *>i  10.40.9.1\/32     10.10.1.1                0    100      0 400 i\n *>i  10.40.19.1\/32    10.10.1.1                0    100      0 400 i<\/code><\/pre>\n<\/div><\/div>\n\n\n\n
\u8a2d\u5b9a\u5909\u66f4\uff08Router5\uff09<\/h4>\n\n\n\n
Router1-Router5\u9593\u3092\u7d4c\u7531\u3059\u308b\u300c10.20.7.1\/32\u300d\u5411\u3051\u306e\u7d4c\u8def\u306eMED\u5024\u3092\u300c400\u300d\u306b\u5909\u66f4\u3057\u3066\u307f\u307e\u3059\u3002<\/p>\n\n\n\n
\u5909\u66f4\u30b3\u30de\u30f3\u30c9<\/span><\/div>
\n
Router5#conf t\nEnter configuration commands, one per line.  End with CNTL\/Z.\nRouter5(config)#ip prefix-list MED seq 10 permit 10.20.7.1\/32\nRouter5(config)#route-map MED permit 10\nRouter5(config-route-map)#match ip address prefix-list MED\nRouter5(config-route-map)#set metric 400\nRouter5(config-route-map)#exit\nRouter5(config)#router bgp 200\nRouter5(config-router)#nei\nRouter5(config-router)#neighbor 192.168.1.1 route-map MED out\nRouter5(config-router)#end<\/code><\/pre>\n<\/div><\/div>\n\n\n\n
\u4e8b\u5f8c\u78ba\u8a8d\uff08Router3\uff09<\/h4>\n\n\n\n
\u3067\u306f\u3001\u78ba\u8a8d\u3057\u3066\u307f\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n\n
Router3 BGP\u30c6\u30fc\u30d6\u30eb<\/span><\/div>
\n
Router3#show ip bgp<\/span>\nBGP table version is 16, local router ID is 10.10.3.1\nStatus codes: s suppressed, d damped, h history, * valid, > best, i - internal,\n              r RIB-failure, S Stale, m multipath, b backup-path, f RT-Filter,\n              x best-external, a additional-path, c RIB-compressed,\n              t secondary path,\nOrigin codes: i - IGP, e - EGP, ? - incomplete\nRPKI validation codes: V valid, I invalid, N Not found\n\n     Network          Next Hop            Metric LocPrf Weight Path\n r>i  10.10.1.1\/32     10.10.1.1                0    100      0 i\n r>i  10.10.2.1\/32     10.10.2.1                0    100      0 i\n *>   10.10.3.1\/32     0.0.0.0                  0         32768 i\n r>i  10.10.4.1\/32     10.10.4.1                0    100      0 i\n *>i  10.20.5.1\/32     10.10.2.1                0    100      0 200 i\n *>i  10.20.6.1\/32     10.10.2.1                0    100      0 200 i\n *>i  10.20.7.1\/32     10.10.2.1                0    100      0 200 i<\/span>\n *>i  10.30.8.1\/32     10.10.2.1              400    100      0 300 i\n *>i  10.40.9.1\/32     10.10.1.1                0    100      0 400 i\n *>i  10.40.19.1\/32    10.10.1.1                0    100      0 400 i<\/code><\/pre>\n<\/div><\/div>\n\n\n\n
\u60f3\u5b9a\u901a\u308aRouter3\u3067\u306fECMP\u3068\u306a\u308b\u7d4c\u8def\u304c\u306a\u304f\u306a\u308a\u3001\u5148\u307b\u3069\u30d9\u30b9\u30c8\u30d1\u30b9\u306b\u306a\u3063\u3066\u3044\u306a\u304b\u3063\u305fnexthop\u300c10.10.2.1\u300d\u306b\u5411\u3044\u3066\u3044\u307e\u3059\u3002<\/p>\n\n\n\n
\u3067\u306f\u3001Router1\u3067MED\u5024\u3092\u78ba\u8a8d\u3057\u3066\u307f\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n\n
Router1 BGP\u30c6\u30fc\u30d6\u30eb<\/span><\/div>
\n
Router1#show ip bgp<\/span>\nBGP table version is 16, local router ID is 10.10.1.1\nStatus codes: s suppressed, d damped, h history, * valid, > best, i - internal,\n              r RIB-failure, S Stale, m multipath, b backup-path, f RT-Filter,\n              x best-external, a additional-path, c RIB-compressed,\n              t secondary path,\nOrigin codes: i - IGP, e - EGP, ? - incomplete\nRPKI validation codes: V valid, I invalid, N Not found\n\n     Network          Next Hop            Metric LocPrf Weight Path\n *>   10.10.1.1\/32     0.0.0.0                  0         32768 i\n r>i  10.10.2.1\/32     10.10.2.1                0    100      0 i\n r>i  10.10.3.1\/32     10.10.3.1                0    100      0 i\n r>i  10.10.4.1\/32     10.10.4.1                0    100      0 i\n *>i  10.20.5.1\/32     10.10.2.1                0    100      0 200 i\n *                     192.168.5.2                            0 400 200 i\n *    10.20.6.1\/32     192.168.5.2                            0 400 200 i\n *>i                   10.10.2.1                0    100      0 200 i\n *    10.20.7.1\/32     192.168.5.2                            0 400 200 i\n *                     192.168.1.2            400             0 200 i<\/span>\n *>i                   10.10.2.1                0    100      0 200 i\n *>i  10.30.8.1\/32     10.10.2.1              400    100      0 300 i\n *>   10.40.9.1\/32     192.168.5.2              0             0 400 i\n *>   10.40.19.1\/32    192.168.5.2              0             0 400 i<\/code><\/pre>\n<\/div><\/div>\n\n\n\n
\u3057\u3063\u304b\u308aMED\u5024\u304c\u300c400\u300d\u306b\u306a\u3063\u3066\u3044\u308b\u3053\u3068\u3082\u308f\u304b\u308a\u3001\u30d9\u30b9\u30c8\u30d1\u30b9\u308210.10.2.1\u306e\u30eb\u30fc\u30bf2\u3092\u5411\u3044\u3066\u308b\u3053\u3068\u304c\u308f\u304b\u308a\u307e\u3059\u3002<\/p>\n\n\n
\n