BGP公网常见问题讲解.ppt

Page * Q3：BGP路由活跃，但在IP路由表中不活跃？ [Quidway]display ip routing-table 24 verbose Route Flags: R - relay, D - download to fib Routing Table : Public Summary Count : 2 Destination: /24 Protocol: Static Process ID: 0 Preference: 60 Cost: 0 NextHop: Neighbour: State: Active Adv Age: 00h00m34s Tag: 0 Priority: medium Label: NULL QoSInfo: 0x0 IndirectID: 0x0 RelayNextHop: Interface: NULL0 TunnelID: 0x0 Flags: D Destination: /24 Protocol: BGP Process ID: 0 Preference: 255 Cost: 0 NextHop: 00 Neighbour: 00 State: Inactive Adv Relied Age: 00h01m02s Tag: 0 Priority: low Label: NULL QoSInfo: 0x0 IndirectID: 0x2 RelayNextHop: Interface: Ethernet0/0/0 TunnelID: 0x0 Flags: R [Quidway] 优先级preference BGP路由不活跃 Page * 路由表的层级 Page * BGP路由常用命令行总结 BGP路由表和IP路由表详细信息同时查看，注意带掩码 display ip routing-table x.x.x.x x.x.x.x verbose //IP路由详细信息 display bgp routing-table x.x.x.x x.x.x.x //BGP路由详细信息 display bgp routing-table statistics //BGP路由总数 display ip routing-table statistics //IP路由总数 display bgp routing-table peer x.x.x.x received-routes //从邻居收到的路由 【注意】 display bgp routing-table peer x.x.x.x advertised-routes //发给邻居的路由 当前版本显示的BGP路由属性是本地存储，并非是真正发送给邻居的 Page * BGP路由属性-选路规则（LAO MEN老男人） 1、Preferred-value（大的优先，本地有效，不传递，Cisco叫weight） 2、Local-Preference（大的优先） 3、Aggregator Automic-Aggregate 4、AS-Path 5、Origin 6、MED 7、eBGPiBGPLocalCrossRemoteCross 8、Next hop(cost) 负载分担选择条件 9、Cluster-List 10、Originator-ID(Router ID) 11、BGP邻居IP地址 Community/Ext-Community(缺省不发，需配置命令peer advertise-community才发) Page * [Quidway-bgp]display bgp routing-table BGP local router ID : Local AS number : 100 Paths: 2 available, 1 best, 1 select BGP routing table entry information of /24: From: 00 (00) Route Du