学校网站建设与维护方案,一起做网站17怎么下单,建站服务器多少钱,制作网站的心得体会路由器#xff1a;路由器是一种典型的网络连接设备#xff0c;用来进行路由选择和报文转发。路由器与它直接相连的网络的跳数为0#xff0c;通过一台路由器可达的网络的跳数为1.路由协议#xff1a;路由器之间维护路由表的规则#xff0c;用以发现路由#xff0c;生成路由… 路由器路由器是一种典型的网络连接设备用来进行路由选择和报文转发。 路由器与它直接相连的网络的跳数为0通过一台路由器可达的网络的跳数为1. 路由协议路由器之间维护路由表的规则用以发现路由生成路由表并引导报文转发。 路由器决策路由关键是路由表转发报文关键是FIB表Forwarding Information Base表。每个路由器至少维护着一张路由表和一张FIB表。 路由表中通常包含 链路层协议发现的路由接口路由或直连路由 网络管理员人工配置的静态路由 动态路由协议主动发现的路由 FIB表指明分组到某网段或某主机应通过路由器的物理接口或逻辑接口发送到达计划路径的下一个路由器当然也可以不经过路由器直达直接相连网络中的主机。 一台路由器保存着一张本地核心管理路由表路由协议也维护着自己的路由表。即本地核心路由表 用来保护协议路由和决策优选路由负责把优选路由下发到FIB由FIB负责指导转发。具体通过display ip routing-table,查看 各种路由协议的优先级和度量值选取路由。协议路由表 即协议主动发现的路由。路由协议可以引入并发布其它协议生成的路由。 例如查看路由表quidwaydis ip routing-table Route Flags: R - relay, D - download to fib ------------------------------------------------------------------------------ Routing Tables: Public Destinations : 20 Routes : 20 Destination/Mask Proto Pre Cost Flags NextHop Interface 10.201.54.215/32 Static 60 0 RD 10.201.81.19 GigabitEthernet1/0/23 10.201.57.128/27 Static 60 0 RD 10.201.81.19 GigabitEthernet1/0/23 10.201.62.0/26 Static 60 0 RD 10.201.81.19 GigabitEthernet1/0/23 10.201.63.4/32 Static 60 0 RD 10.201.81.19 GigabitEthernet1/0/23 10.201.81.16/29 Direct 0 0 D 10.201.81.20 GigabitEthernet1/0/23 10.201.81.20/32 Direct 0 0 D 127.0.0.1 InLoopBack0 10.201.81.23/32 Direct 0 0 D 127.0.0.1 InLoopBack0 10.201.81.24/30 Direct 0 0 D 10.201.81.25 Vlanif30 10.201.81.25/32 Direct 0 0 D 127.0.0.1 InLoopBack0 10.201.81.26/32 Direct 0 0 D 10.201.81.26 Vlanif30 10.201.81.27/32 Direct 0 0 D 127.0.0.1 InLoopBack0 10.201.93.241/32 Direct 0 0 D 127.0.0.1 InLoopBack0 10.201.93.242/32 Static 60 0 RD 10.201.81.26 Vlanif30 127.0.0.0/8 Direct 0 0 D 127.0.0.1 InLoopBack0 127.0.0.1/32 Direct 0 0 D 127.0.0.1 InLoopBack0 127.255.255.255/32 Direct 0 0 D 127.0.0.1 InLoopBack0 138.1.1.1/32 Static 60 0 RD 10.201.81.19 GigabitEthernet1/0/23 138.2.1.1/32 Static 60 0 RD 10.201.81.19 GigabitEthernet1/0/23 138.7.1.1/32 Static 60 0 RD 10.201.81.19 GigabitEthernet1/0/23 255.255.255.255/32 Direct 0 0 D 127.0.0.1 InLoopBack0解释 Route Flags:路由标记R表示该路由是迭代路由D表示该路由下发到FIB表。 Routing Tables说明路由表是公网路由表还是私网路由表。 Destinations目的网络或者主机的总数。 Routes路由总数。 Destination/Mask目的地址和子网掩码。 Proto协议说明是直连、静态还是动态路由。 Pre本条路由加入路由表的优先级。它包括前面所讲的所有路由加上优先级优先级高数值小的便是当前的最佳路由。各协议的路由优先级如下表 表1-1 路由协议及缺省时的路由优先级 路由协议或路由种类 相应路由的优先级 DIRECT 0 OSPF 10 IS-IS 15 STATIC 60 RIP 100 OSPF ASE 150 OSPF NSSA 150 IBGP 255 EBGP 255 注意除直连路由DIRECT外各种路由协议的优先级都可由用户手工进行配置。 Cost路由开销。当到达同一目的地的多条路由具有相同的优先级时它就派上用场了。路由开销小的将成为当前的最佳路由。 提醒Pre用于不同路由协议间路由优先级的比较cost即用于同一种路由协议内部不同路由优先级的比较。 Flags路由标记即路由表头的Route Flags表示路由信息所处状态。 NextHop下一跳地址。说明IP包经过的下一个路由器。 Interface下一跳可达的出接口。说明IP包将从下一个路由器哪一个接口转发。 不过上面的路由表只是路由表简表它只显示激活的路由而完整的路由表还包括未激活的路由。可以通过命令display ip routing-table verbose查看。 例如quidwaydis ip routing-table verbose Route Flags: R - relay, D - download to fib ------------------------------------------------------------------------------ Routing Table : Public Destinations : 20 Routes : 27 Destination: 10.201.54.215/32 Protocol: Static Process ID: 0 Preference: 60 Cost: 0 NextHop: 10.201.81.19 Neighbour: 0.0.0.0 State: Active Adv GotQ Age: 8d05h16m34s Tag: 0 Priority: 0 Label: NULL QoSInfo: 0x0 RelayNextHop: 0.0.0.0 Interface: GigabitEthernet1/0/23 TunnelID: 0x0 Flags: RD Destination: 10.201.54.215/32 Protocol: Static Process ID: 0 Preference: 100 Cost: 0 NextHop: 10.201.81.26 Neighbour: 0.0.0.0 State: Inactive Adv GotQ Age: 8d05h16m34s Tag: 0 Priority: 0 Label: NULL QoSInfo: 0x0 RelayNextHop: 0.0.0.0 Interface: Vlanif30 TunnelID: 0x0 Flags: R Destination: 10.201.57.128/27 Protocol: Static Process ID: 0 Preference: 60 Cost: 0 NextHop: 10.201.81.19 Neighbour: 0.0.0.0 State: Active Adv GotQ Age: 138d23h14m06s Tag: 0 Priority: 0 Label: NULL QoSInfo: 0x0 RelayNextHop: 0.0.0.0 Interface: GigabitEthernet1/0/23 TunnelID: 0x0 Flags: RD Destination: 10.201.57.128/27 Protocol: Static Process ID: 0 Preference: 100 Cost: 0 NextHop: 10.201.81.26 Neighbour: 0.0.0.0 State: Inactive Adv GotQ Age: 138d23h14m06s Tag: 0 Priority: 0 Label: NULL QoSInfo: 0x0 RelayNextHop: 0.0.0.0 Interface: Vlanif30 TunnelID: 0x0 Flags: R Destination: 10.201.62.0/26 Protocol: Static Process ID: 0 Preference: 60 Cost: 0 NextHop: 10.201.81.19 Neighbour: 0.0.0.0 State: Active Adv GotQ Age: 138d23h14m05s Tag: 0 Priority: 0 Label: NULL QoSInfo: 0x0 RelayNextHop: 0.0.0.0 Interface: GigabitEthernet1/0/23 TunnelID: 0x0 Flags: RD Destination: 10.201.62.0/26 Protocol: Static Process ID: 0 Preference: 100 Cost: 0 NextHop: 10.201.81.26 Neighbour: 0.0.0.0 State: Inactive Adv GotQ Age: 138d23h14m08s Tag: 0 Priority: 0 Label: NULL QoSInfo: 0x0 RelayNextHop: 0.0.0.0 Interface: Vlanif30 TunnelID: 0x0 Flags: R Destination: 10.201.63.4/32 Protocol: Static Process ID: 0 Preference: 60 Cost: 0 NextHop: 10.201.81.19 Neighbour: 0.0.0.0 State: Active Adv GotQ Age: 140d23h35m45s Tag: 0 Priority: 0 Label: NULL QoSInfo: 0x0 RelayNextHop: 0.0.0.0 Interface: GigabitEthernet1/0/23 TunnelID: 0x0 Flags: RD Destination: 10.201.63.4/32 Protocol: Static Process ID: 0 Preference: 100 Cost: 0 NextHop: 10.201.81.26 Neighbour: 0.0.0.0 State: Inactive Adv GotQ Age: 140d23h28m08s Tag: 0 Priority: 0 Label: NULL QoSInfo: 0x0 RelayNextHop: 0.0.0.0 Interface: Vlanif30 TunnelID: 0x0 Flags: R Destination: 10.201.81.16/29 Protocol: Direct Process ID: 0 Preference: 0 Cost: 0 NextHop: 10.201.81.20 Neighbour: 0.0.0.0 State: Active Adv Age: 140d23h35m45s Tag: 0 Priority: 0 Label: NULL QoSInfo: 0x0 RelayNextHop: 0.0.0.0 Interface: GigabitEthernet1/0/23 TunnelID: 0x0 Flags: D Destination: 10.201.81.20/32 Protocol: Direct Process ID: 0 Preference: 0 Cost: 0 NextHop: 127.0.0.1 Neighbour: 0.0.0.0 State: Active NoAdv Age: 140d23h35m46s Tag: 0 Priority: 0 Label: NULL QoSInfo: 0x0 RelayNextHop: 0.0.0.0 Interface: InLoopBack0 TunnelID: 0x0 Flags: D Destination: 10.201.81.23/32 Protocol: Direct Process ID: 0 Preference: 0 Cost: 0 NextHop: 127.0.0.1 Neighbour: 0.0.0.0 State: Active NoAdv Age: 140d23h35m46s Tag: 0 Priority: 0 Label: NULL QoSInfo: 0x0 RelayNextHop: 0.0.0.0 Interface: InLoopBack0 TunnelID: 0x0 Flags: D Destination: 10.201.81.24/30 Protocol: Direct Process ID: 0 Preference: 0 Cost: 0 NextHop: 10.201.81.25 Neighbour: 0.0.0.0 State: Active Adv Age: 140d23h28m09s Tag: 0 Priority: 0 Label: NULL QoSInfo: 0x0 RelayNextHop: 0.0.0.0 Interface: Vlanif30 TunnelID: 0x0 Flags: D Destination: 10.201.81.25/32 Protocol: Direct Process ID: 0 Preference: 0 Cost: 0 NextHop: 127.0.0.1 Neighbour: 0.0.0.0 State: Active NoAdv Age: 140d23h28m09s Tag: 0 Priority: 0 Label: NULL QoSInfo: 0x0 RelayNextHop: 0.0.0.0 Interface: InLoopBack0 TunnelID: 0x0 Flags: D Destination: 10.201.81.26/32 Protocol: Direct Process ID: 0 Preference: 0 Cost: 0 NextHop: 10.201.81.26 Neighbour: 0.0.0.0 State: Active NoAdv Age: 140d23h28m05s Tag: 0 Priority: 0 Label: NULL QoSInfo: 0x0 RelayNextHop: 0.0.0.0 Interface: Vlanif30 TunnelID: 0x0 Flags: D Destination: 10.201.81.27/32 Protocol: Direct Process ID: 0 Preference: 0 Cost: 0 NextHop: 127.0.0.1 Neighbour: 0.0.0.0 State: Active NoAdv Age: 140d23h28m54s Tag: 0 Priority: 0 Label: NULL QoSInfo: 0x0 RelayNextHop: 0.0.0.0 Interface: InLoopBack0 TunnelID: 0x0 Flags: D Destination: 10.201.93.241/32 Protocol: Direct Process ID: 0 Preference: 0 Cost: 0 NextHop: 127.0.0.1 Neighbour: 0.0.0.0 State: Active Adv Age: 140d23h42m01s Tag: 0 Priority: 0 Label: NULL QoSInfo: 0x0 RelayNextHop: 0.0.0.0 Interface: InLoopBack0 TunnelID: 0x0 Flags: D Destination: 10.201.93.242/32 Protocol: Static Process ID: 0 Preference: 60 Cost: 0 NextHop: 10.201.81.26 Neighbour: 0.0.0.0 State: Active Adv GotQ Age: 138d23h13m26s Tag: 0 Priority: 0 Label: NULL QoSInfo: 0x0 RelayNextHop: 0.0.0.0 Interface: Vlanif30 TunnelID: 0x0 Flags: RD Destination: 127.0.0.0/8 Protocol: Direct Process ID: 0 Preference: 0 Cost: 0 NextHop: 127.0.0.1 Neighbour: 0.0.0.0 State: Active NoAdv Age: 140d23h42m07s Tag: 0 Priority: 0 Label: NULL QoSInfo: 0x0 RelayNextHop: 0.0.0.0 Interface: InLoopBack0 TunnelID: 0x0 Flags: D Destination: 127.0.0.1/32 Protocol: Direct Process ID: 0 Preference: 0 Cost: 0 NextHop: 127.0.0.1 Neighbour: 0.0.0.0 State: Active NoAdv Age: 140d23h42m10s Tag: 0 Priority: 0 Label: NULL QoSInfo: 0x0 RelayNextHop: 0.0.0.0 Interface: InLoopBack0 TunnelID: 0x0 Flags: D Destination: 127.255.255.255/32 Protocol: Direct Process ID: 0 Preference: 0 Cost: 0 NextHop: 127.0.0.1 Neighbour: 0.0.0.0 State: Active NoAdv Age: 140d23h42m10s Tag: 0 Priority: 0 Label: NULL QoSInfo: 0x0 RelayNextHop: 0.0.0.0 Interface: InLoopBack0 TunnelID: 0x0 Flags: D Destination: 138.1.1.1/32 Protocol: Static Process ID: 0 Preference: 60 Cost: 0 NextHop: 10.201.81.19 Neighbour: 0.0.0.0 State: Active Adv GotQ Age: 140d23h36m37s Tag: 0 Priority: 0 Label: NULL QoSInfo: 0x0 RelayNextHop: 0.0.0.0 Interface: GigabitEthernet1/0/23 TunnelID: 0x0 Flags: RD Destination: 138.1.1.1/32 Protocol: Static Process ID: 0 Preference: 100 Cost: 0 NextHop: 10.201.81.26 Neighbour: 0.0.0.0 State: Inactive Adv GotQ Age: 140d23h29m01s Tag: 0 Priority: 0 Label: NULL QoSInfo: 0x0 RelayNextHop: 0.0.0.0 Interface: Vlanif30 TunnelID: 0x0 Flags: R Destination: 138.2.1.1/32 Protocol: Static Process ID: 0 Preference: 60 Cost: 0 NextHop: 10.201.81.19 Neighbour: 0.0.0.0 State: Active Adv GotQ Age: 140d23h36m38s Tag: 0 Priority: 0 Label: NULL QoSInfo: 0x0 RelayNextHop: 0.0.0.0 Interface: GigabitEthernet1/0/23 TunnelID: 0x0 Flags: RD Destination: 138.2.1.1/32 Protocol: Static Process ID: 0 Preference: 100 Cost: 0 NextHop: 10.201.81.26 Neighbour: 0.0.0.0 State: Inactive Adv GotQ Age: 140d23h29m01s Tag: 0 Priority: 0 Label: NULL QoSInfo: 0x0 RelayNextHop: 0.0.0.0 Interface: Vlanif30 TunnelID: 0x0 Flags: R Destination: 138.7.1.1/32 Protocol: Static Process ID: 0 Preference: 60 Cost: 0 NextHop: 10.201.81.19 Neighbour: 0.0.0.0 State: Active Adv GotQ Age: 140d23h36m38s Tag: 0 Priority: 0 Label: NULL QoSInfo: 0x0 RelayNextHop: 0.0.0.0 Interface: GigabitEthernet1/0/23 TunnelID: 0x0 Flags: RD Destination: 138.7.1.1/32 Protocol: Static Process ID: 0 Preference: 100 Cost: 0 NextHop: 10.201.81.26 Neighbour: 0.0.0.0 State: Inactive Adv GotQ Age: 140d23h29m01s Tag: 0 Priority: 0 Label: NULL QoSInfo: 0x0 RelayNextHop: 0.0.0.0 Interface: Vlanif30 TunnelID: 0x0 Flags: R Destination: 255.255.255.255/32 Protocol: Direct Process ID: 0 Preference: 0 Cost: 0 NextHop: 127.0.0.1 Neighbour: 0.0.0.0 State: Active NoAdv Age: 140d23h42m11s Tag: 0 Priority: 0 Label: NULL QoSInfo: 0x0 RelayNextHop: 0.0.0.0 Interface: InLoopBack0 TunnelID: 0x0 Flags: D解释 注意这里的Routes比刚才的多了是因为将未激活的路由条数加进来了。此外还多出其它一些项目 Process ID路由协议的进程号。 Neighbour邻居。 State路由的状态包括有 Active:激活的路由 Invalid:无效的路由 Inactive非激活的路由 NoAdv:不充许发布的路由 Adv可以发布的路由 Del:即将要删除的路由 GotQ:迭代到下一跳及出接口的路由或者迭代到隧道的路由 WatiQ:没有迭代到下一跳及出接口的路由或者迭代到隧道的路由 Stale:带Stale标记的路由在GR中使用 Age:路由有存活时间。 Tag:路由管理标识。 Priority优先级。 LabelMPLS分配的标签。 QoSInfoQoS信息。 RelayNextHop迭代下一跳。 Interface迭代出接口。 Tunnel ID隧道ID。 SecTunnel ID备份隧道ID。 BkNextHop备份出接口。 Route of Packet Load-balance显示逐包软转发查询时所使用的路由的信息 前面说过华为路由器还有一个FIB负责指引报文转发。路由表选择出路由后路由表就会将已经激活的路由下发到FIB中。由于FIB表进行转发。 FIB表根据匹配最长匹配原则。即查找FIB表时报文的目的地址和FIB中各表项的掩码进行“逻辑与”运算将得到的地址与FIB表项中的网络地址匹配并选择最长匹配的FIB表项进行报文转发。 附注关于迭代路由的解释摘抄网上的 我对路由迭代的理解 通常路由的下一跳是路由器某个接口的同网段地址但是存在这样的情形 A ____B______D___E \____C_____/ 路由器A、B、C、D间运行IGP路由协议而路由器E不参与为了使A能到达E需要在A上配置静态路由A可以经由B或者C到达D再到达E那么我们可以在A上配置到E的2条路由 E 下一跳B E 下一跳C 备用 当A到B的链路出现问题 A __X_B______D___E \____C_____/ 下一跳到C的路由起作用了可以正常工作。 但是如果是B-D的链路出问题怎么办呢看下图 A ____B__X___D___E \____C_____/ A并不知道这一点仍然将到E的报文向B转发结果当然是不通了。 解决的办法就是在A上配置迭代路由 E 下一跳D A到E具体走B还是走C取决于A到D是走B还是走C 而A到D具体是走B还是走C则由IGP路由协议动态算出这样无论是A-B的链路出现问题还是B-D的链路出现问题都不会影响A-E的转发。 有人要问为什么不让E也参与IGP不使用静态路由不就不会出类似问题么? 1、在真实的组网环境中很可能A\B\C\D属于同一个管理区域E属于另一个管理区域互相之间不允许运行IGP路由协议。 2、A-D间可能采用了某种隧道技术可能B/C根本就不知道E的存在使用IGP路由协议也不能解决。 本文转自 独钩寒江雪 51CTO博客原文链接http://blog.51cto.com/bennie/265440如需转载请自行联系原作者
