Five methods for transferring default routes through RIP

Figure 5 Ways of passing the default route through RIP: Experiment on passing the default route is as follows. The default reason for passing the default route through RIP is 1: default-information originateR1: www.2cto.com interface Loopback0ip address 1.1.1.1 255.255.0interface Loopback1ip address 11.11.11.11 255.255.255.0interface serial/1ip address 12.0.0.1 255.255.255.0router ripversion 2 network 11.0.0.0network 12.0.0no auto-summary R2: interface serial/1ip address 12.0.0.2 255.255.255.0interface serial/2ip address 23.0.0.2 255.255.255.0router ripversion 2 network 12.0.0.0network protocol auto-summaryR3: interface serial/1ip address 23.0.0.3 protocol ripversion 2 network protocol auto-summar
R1 route table 1.0.0.0/24 is subnetted, 1 subnetsC 1.1.1.0 is directly connected, Loopback0 23.0.0.0/24 is subnetted, 1 subnetsR 23.0.0.0 [120/1] via 12.0.0.2, 00:00:02, serial/1 11.0.0.0/24 is subnetted, 1 subnetsC 11.11.11.0 is directly connected, Loopback1 12.0.0.0/24 is subnetted, 1 subnetsC 12.0.0.0 is directly connected, serial/1R2 route table: www.2cto.com 23.0.0.0/24 is subnetted, 1 subnetsC 23.0.0.0 is directly connected, serial/2 11.0.0.0/24 is subnetted, 1 subnetsR 11.11.11.0 [120/1] via 12.0.0.1, 00:00:20, serial/1 12.0.0.0/24 is subnetted, 1 subnetsC 12.0.0.0 is directly connected, serial/1
R3 route table: 23.0.0.0/24 is subnetted, 1 subnetsC 23.0.0.0 is directly connected, serial/1 11.0.0.0/24 is subnetted, 1 subnetsR 11.11.11.0 [120/2] via 23.0.0.2, 00:00:20, serial/1 12.0.0.0/24 is subnetted, 1 subnetsR 12.0.0.0 [120/1] via 23.0.0.2, 00:00:20, serial/1 R2 # ping 1.1.1.1 Type escape sequence to abort. sending 5, 100-byte ICMP Echos to 1.1.1.1, timeout is 2 seconds :..... success rate is 0 percent (0/5) is not routed through www.2cto.com on R1: R1 (config) # router ripR1 (config-router) # default-information originate // you can add a route-map or press enter to directly press enter to view the effect.
R1 route table 1.0.0.0/24 is subnetted, 1 subnetsC 1.1.1.0 is directly connected, Loopback0 23.0.0.0/24 is subnetted, 1 subnetsR 23.0.0.0 [120/1] via 12.0.0.2, 00:00:01, serial/1 11.0.0.0/24 is subnetted, 1 subnetsC 11.11.11.0 is directly connected, Loopback1 12.0.0.0/24 is subnetted, 1 subnetsC 12.0.0.0 is directly connected, serial/1R2 route table: 23.0.0.0/24 is subnetted, 1 subnetsC 23.0.0.0 is directly connected, serial/2 11.0.0.0/24 is subnetted, 1 subnetsR 11.11.11.0 [120/1] via 12.0.0.1, 00:00:19, serial/1 // indicates that the detailed route can issue 12.0.0.0/24 is subnetted, 1 subnetsC 12.0.0.0 is directly connected, serial/1R * 0.0.0.0/0 [120/1] via 12.0.0.1, 00:00:19, serial/1 // The default route is displayed.
R3 route table: www.2cto.com 23.0.0.0/24 is subnetted, 1 subnetsC 23.0.0.0 is directly connected, serial/1 11.0.0.0/24 is subnetted, 1 subnetsR 11.11.11.0 [120/2] via 23.0.0.2, 00:00:25, serial/1 12.0.0.0/24 is subnetted, 1 subnetsR 12.0.0.0 [120/1] via 23.0.0.2, 00:00:25, serial/1R * 0.0.0.0/0 [120/2] via 23.0.0.2, 00:00:25, serial/1R2 # ping 1.1.1.1 Type escape sequence to abort. sending 5, 100-byte ICMP Echos to 1.1.1.1, timeout is 2 seconds :!!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 172/249/360 ms can indicate that the default route has an effect on R1: R1 (config) # router ripR1 (config-router) # default-information originate route-map QQ // you can view the R2 route table by name: 23.0.0.0/24 is subnetted, 1 subnetsC 23.0.0.0 is directly connected, serial/2 11.0.0.0/24 is subnetted, 1 subnetsR 11.11.11.0 [120/1] via 12.0.0.1, 00:00:14, serial/1 12.0.0.0/24 is subnetted, 1 subnetsC 12.0. 0.0 is directly connected, serial/1 found that the default route is no longer available. However, when I use route-map QQ to match the 1.1.1.0/24 route, R1 (config) # ip prefix-list 1 per 1.1.1.0/24R1 (config) # route-map QQ www.2cto.com R1 (config-route-map) # match ip add prefix-list 1
In the R2 route table: 23.0.0.0/24 is subnetted, 1 subnetsC 23.0.0.0 is directly connected, serial/2 11.0.0.0/24 is subnetted, 1 subnetsR 11.11.11.0 [120/1] via 12.0.0.1, 00:00:03, serial/1 12.0.0.0/24 is subnetted, 1 subnetsC 12.0.0.0 is directly connected, serial/1R * 0.0.0.0/0 [120/1] via 12.0.0.1, 00:00:03, in the summary, the default-information originate API can pass the default route to the network. No default route exists in the route table. If route-map is added, only a route entry that matches itself in the route table can send default routes to other routers. Route entries can be directly connected, learned from lab, or static routes. method 2: manually create a default route entry to the NULL0 port and re-distribute it on R1: R1 (config) # ip route 0.0.0.0 0.0.0.0 null 0R1 (config) # router ripR1 (config-router) # redistribute static metric 2 // The default measurement of static Routing in RIP is 1, you must specify the measurement value, or use the default-metric command to set the default seed measurement value. Because the default RIP seed measurement value is infinite, only the redistribution is static, and the measurement value can be left unspecified) now observe the R1 route table: 1.0.0.0/24 is subnetted, 1 subnetsC 1.1.1.0 is directly connected, Loopback0 23.0.0.0/24 is subnetted, 1 subnetsR 23.0.0.0 [120/1] via 12.0.0.2, 00:00:08, serial/1 11.0.0.0/24 is subnetted, 1 subnetsC 11.11.11.0 is directly connected, Loopback1 12.0.0.0/24 is subnetted, 1 subnetsC 12.0.0.0 is directly connected, serial/1 S * 0.0.0.0/0 is directly connected, Null0 // manually created
R2 route table: www.2cto.com 23.0.0.0/24 is subnetted, 1 subnetsC 23.0.0.0 is directly connected, serial/2 11.0.0.0/24 is subnetted, 1 subnetsR 11.11.11.0 [120/1] via 12.0.0.1, 00:00:11, serial/1 12.0.0.0/24 is subnetted, 1 subnetsC 12.0.0.0 is directly connected, serial/1R * 0.0.0.0/0 [120/2] via 12.0.0.1, 00:00:11, serial/1 // The passed default route metric 2 is set during redistribution.
R3 route table: 3.0.0.0/24 is subnetted, 1 subnetsC 3.3.3.0 is directly connected, Loopback0 leading/24 is subnetted, 1 subnetsC 23.0.0.0 is directly connected, serial/1 11.0.0.0/24 is subnetted, 1 subnetsR 11.11.11.0 [120/2] via 23.0.0.2, 00:00:06, serial/1 // will not suppress details sent 12.0.0.0/24 is subnetted, 1 subnetsR 12.0.0.0 [120/1] via 23.0.0.2, 00:00:06, serial/1R * 0.0.0.0/0 [120/3] via 23.0.0.2, 00:00:06, Se The default route is also available on rial/1 // R3. Note: If you create a manually created default route, the default route will not be transmitted from this interface and the interface that can reach the next hop address. this is because of horizontal segmentation. In RIP, horizontal segmentation is enabled by default. Default route passing method 3: manually create a static default route. In the RIP process, use the NETWORK to declare R1 (config) # ip route 0.0.0.0 0.0.0.0 null 0R1 (config) # router ripR1 (config-router) # net 0.0.0.0R1 route table: 1.0.0.0/24 is subnetted, 1 subnetsC 1.1.1.0 is directly connected, Loopback0 23.0.0.0/24 is subnetted, 1 subnetsR 23.0.0.0 [120/1] via 12.0.0.2, 00:00:14, serial/1 11.0.0.0/24 is subnetted, 1 subnetsC 11.11.11.0 is directly connected, Loopback1 12.0.0.0/24 is subnetted, 1 subnetsC 12.0.0.0 is directly connected, serial/1 S * 0.0.0.0/0 is directly connected, route table on Null0R2: www.2cto.com 1.0.0.0/24 is subnetted, 1 subnetsR 1.1.1.0 [120/1] via 12.0.0.1, 00:00:05, this route is also declared to be learned by R2 23.0.0.0/24 is subnetted, 1 subnetsC 23.0.0.0 is directly connected, serial/2 11.0.0.0/24 is subnetted, 1 subnetsR 11.11.11.0 [120/1] via 12.0.0.1, 00:00:06, serial/1 12.0.0.0/24 is subnetted, 1 subnetsC 12.0.0.0 is directly connected, serial/1R * 0.0.0.0/0 [120/1] via 12.0.0.1, 00:00:06, serial/1 // default route passed
If you change the creation of a static route to R1 (config) # ip route 0.0.0.0 0.0.0.0 s2/1R2 route table 23.0.0.0/24 is subnetted, 1 subnetsC 23.0.0.0 is directly connected, serial/2 11.0.0.0/24 is subnetted, 1 subnetsR 11.11.11.0 [120/1] via 12.0.0.1, 00:00:14, serial/1 12.0.0.0/24 is subnetted, 1 subnetsC 12.0.0.0 is directly connected, serial/1 // The default route is missing.
Conclusion: manually create a default route after 0.0.0.0 is declared in the RIP process, although the default route can be passed, it also announces the unadvertised networks, resulting in other routers having the route information of these networks. Note: If you manually create a default route, the default route is not transmitted from this interface and the interface that can reach the next hop address (same as method 3). The default route method is 4: manually create the default route to NULL0, then, manually summarize the default route ip address summary-address rip 0.0.0.0 0.0.0r1 (config) # ip route 0.0.0.0 0.0.0.0 nu 0R1 (config) under the interface for transmitting the default route) # int s2/1R1 (config-if) # ip summary-address rip 0.0.0.0 0.0.0.0
View R1 route table: www.2cto.com 1.0.0.0/24 is subnetted, 1 subnetsC 1.1.1.0 is directly connected, Loopback0 23.0.0.0/24 is subnetted, 1 subnetsR 23.0.0.0 [120/1] via 12.0.0.2, 00:00:12, serial/1 11.0.0.0/24 is subnetted, 1 subnetsC 11.11.11.0 is directly connected, Loopback1 12.0.0.0/24 is subnetted, 1 subnetsC 12.0.0.0 is directly connected, serial/1 S * 0.0.0.0/0 is directly connected, route table of Null0R2: 23.0.0. 0/24 is subnetted, 1 subnetsC 23.0.0.0 is directly connected, serial/2 12.0.0.0/24 is subnetted, 1 subnetsC 12.0.0.0 is directly connected, serial/1R * 0.0.0.0/0 [120/1] via 12.0.0.1, 00:00:12, serial/1 // The default route is available, but the route 11.11.11.0 is unavailable.
If you do this on R1 (config) # ip route 0.0.0.0 0.0.0.0 s2/1R2 route table: 23.0.0.0/24 is subnetted, 1 subnetsC 23.0.0.0 is directly connected, serial/2 12.0.0.0/24 is subnetted, 1 subnetsC 12.0.0.0 is directly connected, serial/1R * 0.0.0.0/0 [120/1] via 12.0.0.1, 00:00:06, serial/1 // The default route is still being summarized: the default route is transferred by means of manual summarization, with directionality. That is, the aggregation on which interface will transmit the default route from that interface, it does not care about the created default route interface and Next Hop address (note that the comparison with method 2 and method 3 indicates manual summary due to horizontal segmentation) however, this will cause a routing loop. Therefore, we recommend that you manually create the default routing interface to write. Null0, In this interface will suppress in addition to the static routing details of the route (also pay attention to the comparison of this sentence said www.2cto.com to pass the default Routing Method 5: ip default-networkR1 (config) # ip default-network 1.0.0.0 view R1 route table: * 1.0.0.0/24 is subnetted, 1 subnets // multiple * numbers C 1.1.1.0 is directly connected, Loopback0 23.0.0.0/24 is subnetted, 1 subnetsR 23.0.0.0 [120/1] via 12.0.0.2, 00:00:18, serial/1 11.0.0.0/24 is subnetted, 1 subnetsC 11.11.11.0 is directly connected, Loopback1 12.0.0.0/24 is Subnetted, 1 subnetsC 12.0.0.0 is directly connected, route table of serial/1R2: 23.0.0.0/24 is subnetted, 1 subnetsC 23.0.0.0 is directly connected, serial/2 11.0.0.0/24 is subnetted, 1 subnetsR 11.11.11.0 [120/1] via 12.0.0.1, 00:00:17, serial/1 12.0.0.0/24 is subnetted, 1 subnetsC 12.0.0.0 is directly connected, serial/1R * 0.0.0.0/0 [120/1] via 12.0.0.1, 00:00:17, serial/1 // default route appears if command R1 (config) # ip d View the route table for efault-network 1.1.1.0: www.2cto.com 1.0.0.0/8 is variably subnetted, 2 subnets, 2 masksC 1.1.1.0/24 is directly connected, loopback0S 1.0.0.0/8 [1/0] via 1.1.1.0 // a static route 23.0.0.0/24 is subnetted, 1 subnetsR 23.0.0.0 [120/1] via 12.0.0.2, 00:00:09, serial/1 11.0.0.0/24 is subnetted, 1 subnetsC 11.11.11.0 is directly connected, Loopback1 12.0.0.0/24 is subnetted, 1 subnetsC 12.0.0.0 is d Irectly connected: route table 23.0.0.0/24 is subnetted, 1 subnetsC route is directly connected, serial/2 11.0.0.0/24 is subnetted, 1 subnetsR 11.11.11.0 [120/1] via 12.0.0.1, 00:00:10, serial/1 12.0.0.0/24 is subnetted, 1 subnetsC 12.0.0.0 is directly connected, serial/1 // if there is no default route, it indicates that the main class cannot be details R1 (config) # ip default-network 23.0.0.0 1.0.0.0/24 is subnetted, 1 subnetsC 1.1.1.0 is direct Ly connected, Loopback0 * 23.0.0.0/24 is subnetted, 1 subnetsR * 23.0.0.0 [120/1] via 12.0.0.2, 00:00:14, serial/1 11.0.0.0/24 is subnetted, 1 subnetsC 11.11.11.0 is directly connected, loopback1 12.0.0.0/24 is subnetted, 1 subnetsC 12.0.0.0 is directly connected, serial/1R2 23.0.0.0/24 is subnetted, 1 subnetsC restart is directly connected, serial/2 11.0.0.0/24 is subnetted, 1 subnetsR 11.11.11. 0 [120/1] via 12.0.0.1, 00:00:07, serial/1 12.0.0.0/24 is subnetted, 1 subnetsC 12.0.0.0 is directly connected, if the default-network is a network that is not found in R1. Www.2cto.com Summary: ip default-network must be followed by the primary network. If it is not followed by the primary class, it is followed by a subnet or address, a static route is automatically generated. A primary route is a prerequisite: 1: A directly connected route can be sent. 2: If the route table does not exist, no route is sent. 3: The learned route can be sent, but it will not be sent from the interface that learns this route, if the sent metric value is 16 from other protocols, the other routers do not accept it. 4: The created primary-class static route can also be sent out. If the static route is followed by the outbound interface and the next hop address, it will not pass the xjk2131650 from this interface and the interface that can reach the next hop address.