【问题现象】 客户在华北区购买专线访问托管区物理机，新购买专线2，把专线流量全部切换到专线2，客户走公网流量还走原专线1路由器，但切换后访问公网有1000多ms的大延时，拓扑图如下 
处理过程【处理过程】 查看客户配置脚本，如下
专线交换机CE5850 ip route-static 10.86.0.0 255.255.240.0 10.7.4.9 track bfd-session zhuhai_unicom
ip route-static 10.86.0.0 255.255.240.0 10.7.4.5 preference 80
ip route-static 10.86.16.0 255.255.255.0 10.7.4.9 track bfd-session zhuhai_unicom
ip route-static 10.86.16.0 255.255.255.0 10.7.4.5 preference 80
ip route-static 10.86.31.0 255.255.255.0 10.7.4.9 track bfd-session zhuhai_unicom
ip route-static 10.86.31.0 255.255.255.0 10.7.4.5 preference 80
ip route-static 10.86.192.0 255.255.255.0 10.7.4.9 track bfd-session zhuhai_unicom
ip route-static 10.86.192.0 255.255.255.0 10.7.4.5 preference 80
ip route-static 10.136.86.0 255.255.255.0 10.7.4.9 track bfd-session zhuhai_unicom
ip route-static 10.136.86.0 255.255.255.0 10.7.4.5 preference 80
客户防火墙 ip route-static 10.0.3.0 24 10.86.4.250 track 2
ip route-static 10.0.3.0 24 10.86.4.242 preference 100
ip route-static 10.0.96.0 24 10.86.4.250 track 2
ip route-static 10.0.96.0 24 10.86.4.242 preference 100
ip route-static 10.6.0.0 16 10.86.4.250 track 2
ip route-static 10.6.0.0 16 10.86.4.242 preference 100
ip route-static 10.88.22.0 24 10.86.4.250 track 2
ip route-static 10.88.22.0 24 10.86.4.242 preference 100
ip route-static 10.136.0.0 16 10.86.4.250 track 2
ip route-static 10.136.0.0 16 10.86.4.242 preference 100
ip route-static 10.136.0.0 18 10.86.4.250 track 2
ip route-static 10.136.0.0 18 10.86.4.242 preference 100
ip route-static 10.136.1.0 24 10.86.4.250 track 2
ip route-static 10.136.1.0 24 10.86.4.242 preference 100
ip route-static 10.136.64.0 20 10.86.4.250 track 2
ip route-static 10.136.64.0 20 10.86.4.242 preference 100
ip route-static 10.136.80.0 22 10.86.4.250 track 2
ip route-static 10.136.80.0 22 10.86.4.242 preference 100
ip route-static 10.136.84.0 24 10.86.4.250 track 2
ip route-static 10.136.84.0 24 10.86.4.242 preference 100
ip route-static 10.136.85.0 24 10.86.4.250 track 2
ip route-static 10.136.85.0 24 10.86.4.242 preference 100
ip route-static 10.136.88.0 21 10.86.4.250 track 2
ip route-static 10.136.88.0 21 10.86.4.242 preference 100
ip route-static 10.136.96.0 20 10.86.4.250 track 2
ip route-static 10.136.96.0 20 10.86.4.242 preference 100
ip route-static 10.136.128.0 17 10.86.4.250 track 2
ip route-static 10.136.128.0 17 10.86.4.242 preference 100
ip route-static 10.254.1.0 24 10.86.4.250 track 2
ip route-static 10.254.1.0 24 10.86.4.242 preference 100
ip route-static 88.88.8.0 24 10.86.4.250 track 2
ip route-static 88.88.8.0 24 10.86.4.242 preference 100
ip route-static 172.20.8.0 24 10.86.4.250 track 2
ip route-static 172.20.8.0 24 10.86.4.242 preference 100
ip route-static 172.20.241.0 24 10.86.4.250 track 2
ip route-static 172.20.241.0 24 10.86.4.242 preference 100
ip route-static 192.168.0.0 16 10.86.4.250 track 2
ip route-static 192.168.0.0 16 10.86.4.242 preference 100
查看客户tracert图，如下图所示，左侧为访问托管区，右侧为访问公网，发现第一跳公网地址为大延时，但出口路由器禁tracert无法判断是否大延时 
在客户防火墙上建测试口设备为内网地址10.86.31.200/32测试公网地址结果同上，说明故障点在防火墙以上节点。在客户专线1路由器上起测试地址163.177.151.110（百度地址），测试结果同上，说明故障点在路由器与防火墙二者之一。在专线1路由器上查看路由，发现到10.86.31.200的下一跳不是防火墙而是路由器，在专线交换机上查看路由协议发现路由器与专线交换机之间运行OSPF，且引入了静态路由，命令如下 #
ospf 10 router-id 10.7.4.6
import-route direct route-policy in_ospf
import-route static route-policy in_ospf
area 0.0.0.0
network 10.6.32.0 0.0.0.255
network 10.7.4.4 0.0.0.3
network 10.7.4.8 0.0.0.3
#
之前变更配置包括了到10.86.31.200的静态路由，如下所示，导致此静态路由引入到了OSPF中，通告给邻居专线1路由器， ip route-static 10.86.31.0 255.255.255.0 10.7.4.9 track bfd-session zhuhai_unicom
ip route-static 10.86.31.0 255.255.255.0 10.7.4.5 preference 80
到此故障点已找到，内网10.86.31.0访问公网的来回路径不一致，回程路径经过专线，经过测试专线延时1000多毫秒。 解决方法，在客户专线1 路由器上添加静态路由到100.86.31.0/24，使来回路径一致。 根因来回路径不一致和专线延时大是导致客户访问公网延时大的根因。 建议与总结延时大要配合命令tracert命令查看，还要结合来回的路径，一般采取分段排查的办法确认故障点。
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