BGP\u5354\u8b70\u662f\u58f9\u500b\u8def\u5f91\u77e2\u91cf\u8def\u7531\u5354\u8b70\uff0c\u4e5f\u5c31\u662f\u8aaa\uff0c\u5b83\u7684\u5de5\u4f5c\u5c31\u662f\u5728\u81ea\u4e3b\u7cfb\u7d71\u9593\u4ea4\u63db\u8def\u7531\u4fe1\u606f\uff0c\u4ee5\u4fbf\u767c\u73fe\u8a2a\u554f\u4e92\u806f\u7db2\u67d0\u8655\u6578\u64da\u7684\u6700\u6709\u6548\u8def\u5f91\u3002\u6bcf\u500bBGP\u8def\u7531\u5668\u901a\u904e\u9130\u5c45\u8072\u540d\u8207\u5468\u908a\u7684\u58f9\u500b\u6216\u591a\u500b\u8def\u7531\u5668\u9023\u63a5\u3002\u58f9\u65e6\u5efa\u7acb\u4e86\u9130\u5c45\u95dc\u7cfb\uff0c\u9019\u4e9bBGP\u8def\u7531\u5668\u4e4b\u9593\u5c31\u6703\u76f8\u4e92\u4ea4\u63db\u8def\u7531\u4fe1\u606f\u3002\u64da\u6211\u6700\u8fd1\u58f9\u6b21\u7d71\u8a08\uff0c\u6574\u500b\u4e92\u806f\u7db2\u4e0a\u6709\u5927\u7d0412.5\u842c\u500b\u8def\u7531\u4fe1\u606f\uff0c\u56e0\u6b64\u8981\u914d\u5099\u58f9\u500b\u5f37\u5927\u7684\u8def\u7531\u5668\u624d\u80fd\u5c07\u6240\u6709BGP\u8def\u7531\u4fe1\u606f\u63a5\u6536\u4e0b\u4f86\u3002<\/p>\n
\u4ec0\u9ebd\u662f BGP \u6700\u4f73\u8def\u5f91\u9078\u64c7\u7b97\u6cd5?
\n\u7531\u65bc\u6574\u500b\u4e92\u806f\u7db2\u7684BGP\u8def\u7531\u8868\u6709\u8d85\u904e20\u842c\u500b\u8def\u7531\uff0c\u540c\u6642\u58f9\u500bBGP\u8def\u7531\u5668\u53ef\u80fd\u5f9e\u591a\u500b\u4f86\u6e90\u6536\u5230\u591a\u4efd\u7684\u8def\u7531\u8868\uff0c\u56e0\u6b64\u80af\u5b9a\u6703\u6709\u58f9\u7a2e\u65b9\u6cd5\u53ef\u4ee5\u6bd4\u8f03\u4e0d\u540c\u7684BGP\u8def\u7531\u8868\uff0c\u4e26\u5f9e\u4e2d\u9078\u64c7\u6700\u4f73\u7684\u8def\u7531\u65b9\u6848\u3002\u9019\u7a2e\u65b9\u6cd5\u5c31\u662fBGP\u6700\u4f73\u8def\u5f91\u9078\u64c7\u7b97\u6cd5\u3002\u53ef\u80fd\u59b3\u6703\u8a3b\u610f\u5230\uff0cCiscoBGP\u8def\u7531\u5668\u6703\u5c07\u61c9\u7528\u6b0a\u91cd(weight)\u4f5c\u70ba\u8def\u7531\u8868\u7684\u7b2c\u58f9\u6a19\u6e96\uff0c\u800c\u5176\u5b83\u54c1\u724c\u7684\u8def\u7531\u5668\u5247\u4e0d\u662f\u9019\u6a23\u3002Cisco\u7684\u5b98\u65b9BGP\u6700\u4f73\u8def\u5f91\u9078\u64c7\u7b97\u6cd5\u6587\u6a94\u4e2d\u8a73\u7d30\u5217\u660e\u4e86\u6240\u53c3\u8003\u7684\u5404\u9805\u6a19\u6e96\u3002\u63a5\u4e0b\u4f86\u6211\u6703\u5217\u51fa\u6bcf\u7a2e\u6a19\u6e96\u4e26\u7d66\u51fa\u89e3\u91cb\u548c\u7bc4\u4f8b\u3002\u9ed8\u8a8d\u60c5\u6cc1\u4e0b\uff0cBGP\u6700\u4f73\u8def\u5f91\u90fd\u662f\u57fa\u65bc\u6700\u77ed\u81ea\u6cbb\u7cfb\u7d71(AS)\u7684\u539f\u7406\u5f97\u51fa\u7684\u3002\u4e0d\u904e\u5f88\u591a\u6642\u5019\uff0c\u8af8\u5982weight\uff0clocalpreference\u4ee5\u53caMED\u9019\u6a23\u7684\u6a19\u6e96\u90fd\u662f\u7db2\u7d61\u7ba1\u7406\u54e1\u81ea\u884c\u8a2d\u5b9a\u7684\u3002<\/p>\n
\u63a5\u4e0b\u4f86\u6211\u5011\u5c31\u6309\u7167BGP\u9078\u64c7\u6700\u4f73\u8def\u5f91\u7684\u53c3\u8003\u9806\u5e8f\u5c07\u9019\u5e7e\u9805\u6a19\u6e96\u4ecb\u7d39\u58f9\u4e0b\uff1a
\n#1 Weight \u2014\u6b0a\u91cd\u662fCisco\u70ba\u672c\u5730\u8def\u7531\u5668\u8a2d\u5b9a\u7684\u81ea\u5b9a\u7fa9\u53c3\u6578\uff0c\u4e26\u4e0d\u96a8\u8def\u7531\u5668\u66f4\u65b0\u800c\u8b8a\u5316\u3002\u5982\u679c\u6307\u5411\u67d0\u58f9IP\u5730\u5740\u7684\u8def\u5f91\u6709\u591a\u689d(\u9019\u5f88\u5e38\u898b)\uff0c\u90a3\u9ebdBGP\u6703\u5c0b\u627e\u6b0a\u91cd\u6700\u9ad8\u7684\u8def\u5f91\u3002\u8a2d\u5b9a\u6b0a\u91cd\u7684\u53c3\u8003\u56e0\u7d20\u5f88\u591a\uff0c\u5305\u62ec\u9130\u5c45\u547d\u4ee4\uff0cas-path\u8a2a\u554f\u5217\u8868\uff0c\u6216\u8005\u8def\u7531\u93e1\u50cf\u7b49\u3002
\n\u3000\u3000#2 Local Preference \u2014 \u672c\u5730\u51fa\u53e3\u512a\u5148\u7d1a\u53c3\u6578\u6703\u544a\u77e5AS\u54ea\u689d\u8def\u5f91\u5177\u6709\u672c\u5730\u512a\u5148\uff0c\u6578\u503c\u8d8a\u9ad8\u512a\u5148\u7d1a\u8d8a\u9ad8\u3002\u9ed8\u8a8d\u70ba100\u3002\u6bd4\u5982\uff1a
\n\u3000\u3000bgp default local-preference 150
\n\u3000\u3000#3 Network or Aggregate\u2014\u9019\u500b\u53c3\u6578\u6703\u9078\u64c7\u672c\u5730\u767c\u8d77\u7684\u7db2\u7d61\u6216\u805a\u5408\u4f5c\u70ba\u8def\u5f91\u3002\u5c07\u7279\u5b9a\u7684\u8def\u5f91\u52a0\u5165\u8def\u7531\u4e2d\uff0c\u6703\u8b93\u8def\u7531\u66f4\u6709\u6548\u7387\uff0c\u540c\u6642\u4e5f\u7bc0\u7701\u4e86\u7db2\u7d61\u7a7a\u9593\u3002\u66f4\u591a\u6709\u95dc\u805a\u5408\u7684\u4fe1\u606f\uff0c\u53ef\u4ee5\u53c3\u8003Cisco\u7684\u6587\u7ae0\u201cUnderstandingRouteAggregation in BGP.\u201d
\n\u3000\u3000#4 Shortest AS_PATH \u2014 BGP \u53ea\u6709\u5728weight, localpreference\u548clocallyoriginated\u76f8\u7576\u63a5\u8fd1\u7684\u6642\u5019\u624d\u4f7f\u7528\u9019\u500b\u53c3\u6578\u3002
\n\u3000\u3000#5 Lowest origin type \u2014 \u9019\u500b\u53c3\u6578\u8655\u7406Interior Gateway Protocol(IGP)\u5354\u8b70\u7684\u512a\u5148\u7d1a\u4f4e\u65bc Exterior Gateway Protocol (EGP)\u5354\u8b70\u3002
\n\u3000\u3000#6 Lowest multi-exit discriminator (MED) \u2014 \u8f03\u4f4e\u7684MED\u503c\u8981\u512a\u65bc\u8f03\u9ad8\u7684MED\u503c\u3002
\n\u3000\u3000#7 eBGP over iBGP \u2014 \u985e\u4f3c\u65bc#5, BGP AS Path \u66f4\u50be\u5411 eBGP \u800c\u4e0d\u662f iBGP\u3002
\n\u3000\u3000#8 Lowest IGP metric \u2014 \u9019\u500b\u53c3\u6578\u50be\u5411\u65bc\u91c7\u7528\u6700\u4f4eIGP\u4f5c\u70baBGP\u4e0b\u58f9\u8df3\u3002
\n\u3000\u3000#9 Multiple paths \u2014 \u9019\u500b\u53c3\u6578\u6c7a\u5b9a\u662f\u5426\u8981\u5728\u8def\u7531\u8868\u4e2d\u88dd\u5165\u591a\u500b\u8def\u5f91\u3002\u53ef\u4ee5\u53c3\u8003 BGPMultipath\u7372\u53d6\u66f4\u591a\u4fe1\u606f\u3002
\n\u3000\u3000#10 External paths \u2014 \u7576\u6240\u6709\u8def\u5f91\u90fd\u70ba\u5916\u90e8\u8def\u5f91\u6642\uff0c\u9078\u64c7\u9996\u5148\u63a5\u6536\u5230\u7684\u8def\u5f91(\u8f03\u8001\u7684\u8def\u5f91)\u3002)
\n\u3000\u3000#11 Lowest router ID \u2014 \u9078\u64c7\u4f86\u81ea\u5177\u6709\u6700\u4f4e\u8def\u7531\u5668ID\u7684BGP\u8def\u7531\u5668\u7684\u8def\u5f91\u3002
\n\u3000\u3000#12 Minimum cluster list \u2014 \u5982\u679c\u591a\u500b\u8def\u5f91\u7684originator\u6216\u8def\u7531\u5668ID\u76f8\u540c\uff0c\u9078\u64c7cluster\u5217\u8868\u9577\u5ea6\u6700\u77ed\u7684\u8def\u5f91\u3002
\n\u3000\u3000#13 Lowest neighbor address \u2014 \u9019\u662f\u6307\u6700\u4f4e\u9130\u5c45\u5730\u5740\u50b3\u4f86\u7684\u8def\u5f91\u3002
\n\u3000\u3000\u6709\u4e9b\u547d\u4ee4\u9700\u8981\u4e0d\u65b7\u7684\u7528\u5230BGP \u53c3\u6578\uff0c\u5b83\u5011\u662fshow ip bgp \u548c show ipbgpsummary\u3002\u5be6\u969b\u4e0a\uff0c\u6211\u66f4\u559c\u6b61\u7d66\u9019\u5169\u500b\u547d\u4ee4\u5275\u5efa\u5225\u540d\uff0c\u4ee5\u4fbf\u80fd\u66f4\u5feb\u6377\u7684\u4f7f\u7528\u5b83\u5011(\u53c3\u8003\u6211\u7684\u6587\u7ae0\u300a\u7528Cisco\u547d\u4ee4\u5225\u540d\u66f4\u6709\u6548\u7684\u8f38\u5165\u547d\u4ee4\u300b)\u3002\u9019\u4e9b\u547d\u4ee4\u53ef\u4ee5\u8b93\u59b3\u5feb\u901f\u7372\u53d6BGP\u4ee5\u53ca\u8207\u8def\u7531\u5668\u7684\u95dc\u7cfb\u3002\u4e0b\u9762\u662f\u4f7f\u7528show ip bgp\u547d\u4ee4\u5f8c\u7684\u60c5\u6cc1\u7bc4\u4f8b\uff1a
\n\u3000\u3000RTA# show ip bgpg
\n\u3000\u3000BGP table version is 14, local router ID is 203.250.15.10
\n\u3000\u3000Status codes: s suppressed, d damped, h history, * valid,>best, i -internal
\n\u3000\u3000Origin codes: i – IGP, e – EGP, ? – incomplete
\n\u3000\u3000Network Next Hop Metric LocPrf Weight Path
\n\u3000\u3000*>i128.213.0.0 128.213.63.2 0 200 0 200 i
\n\u3000\u3000> 192.208.10.0 192.208.10.5 0 300 0 300 i
\n\u3000\u3000*>i200.200.0.0\/16 128.213.63.2 200 0 200 400i
\n\u3000\u3000>i203.250.13.0 203.250.13.41 0 100 0 i
\n\u3000\u3000*>i203.250.14.0 203.250.13.41 0 100 0 i
\n\u3000\u3000*> 203.250.15.0 0.0.0.0 0 32768 i
\n\u3000\u3000\u5e36\u661f\u865f\u7684\u662fBGP\u6700\u4f73\u8def\u5f91\u9078\u64c7\u7b97\u6cd5\u9078\u51fa\u7684\u6700\u4f73\u8def\u5f91\u3002
\n\u3000\u3000\u7e3d\u7d50\uff1a
\n\u3000\u3000\u4e0d\u8ad6\u59b3\u662f\u4f7f\u7528BGP\u7684\u7db2\u7ba1\uff0c\u9084\u662f\u53ea\u662f\u70ba\u4e86CCIE\u6216CCNP\u8003\u8a66\u5b78\u7fd2BGP\u7684\u5b78\u54e1\uff0c\u61c2\u5f97\u9019\u65b9\u9762\u7684\u77e5\u8b58\u90fd\u662f\u975e\u5e38\u6709\u76ca\u7684\u3002\u6b63\u5982\u4e0a\u9762\u770b\u5230\u7684\uff0c\u4f7f\u7528\u53c3\u6578\u548c\u547d\u4ee4\u884c\u7684\u65b9\u5f0f\uff0c\u78ba\u5be6\u53ef\u4ee5\u5feb\u901f\u5be6\u73fe\u6240\u9700\u529f\u80fd\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
BGP\u5354\u8b70\u662f\u58f9\u500b\u8def\u5f91\u77e2\u91cf\u8def\u7531\u5354\u8b70\uff0c\u4e5f\u5c31\u662f\u8aaa\uff0c\u5b83\u7684\u5de5\u4f5c\u5c31\u662f\u5728\u81ea\u4e3b\u7cfb\u7d71\u9593\u4ea4\u63db\u8def\u7531\u4fe1\u606f\uff0c\u4ee5\u4fbf\u767c\u73fe\u8a2a\u554f\u4e92\u806f\u7db2\u67d0\u8655\u6578\u64da\u7684 […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3],"tags":[318],"class_list":["post-749","post","type-post","status-publish","format-standard","hentry","category-cisco","tag-bgp"],"_links":{"self":[{"href":"https:\/\/www.killtest.hk\/index.php\/wp-json\/wp\/v2\/posts\/749","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.killtest.hk\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.killtest.hk\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.killtest.hk\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.killtest.hk\/index.php\/wp-json\/wp\/v2\/comments?post=749"}],"version-history":[{"count":0,"href":"https:\/\/www.killtest.hk\/index.php\/wp-json\/wp\/v2\/posts\/749\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.killtest.hk\/index.php\/wp-json\/wp\/v2\/media?parent=749"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.killtest.hk\/index.php\/wp-json\/wp\/v2\/categories?post=749"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.killtest.hk\/index.php\/wp-json\/wp\/v2\/tags?post=749"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}