ccna 200 301 ebook free download

ccna 200 301 ebook free download.Many causes can cause routing problems. Some routing problems arise because the router has lost a route (possibly for many specific root causes). Some routing problems occur because the routing within the router is incorrect. Given below are some reasons why a router may lose the required route, or have an incorrect route.. The connection between routers is broken.' Commitment point . There is a routing protocol neighbor problem.The routing protocol sends filters that prevent routes from being added to the IPv6 routing table.Incorrect static routes send packets to the wrong next-hop router.A poor subnet design replicates subnets at different locations in the network to the point of misinforming the subnet. For example, see Figure 16-18. when trying to ping host C. host A fails. Host C is located on subnet 33 (2001:DB8:l:33::/64).The traceroute for host C,from host A lists the IPv6 addresses for R1 and R2, but it never stops.Figure 16-18 Incorrect static route creates a routing loop As shown in the figure, there is a routing problem in the loop because of the incorrect static route on R2. Host A can forward IPv6 packets to R1, which is its default router. R1 is able to correctly forward packets sent to host C to router R2. but R2 has subnet 33 incorrectly set up for static routing and is returning to R1. for other root causes of routing problems, check the problem against the list of causes above. Check the interfaces on the router that are supposed to be in up to ensure that these interfaces are working properly. Troubleshoot your own routing protocols. (Chapters 17 and 18 discuss how to troubleshoot OSPFv3 and EIGRPv6, respectively.) It is even important to look for possible misconfiguration of the router interface so that the routing protocol advertises the same subnet number in both locations. also violating the theoretical design rules and overwhelming packets sent to hosts in this IPv6 subnet.Incorrect Static Routing! Routing looks fine, but Traceroute still failsTo conclude this series of scenarios, the last scenario focuses on a specific cause: IPv6 access control lists (ACLs). In the case where a routing problem may exist, you have already learned how the ping and traceroute commands are applied. When ping and traceroute show that the host is able to forward packets, at least to the default router, but not all destinations. the problem could be one of two things.. There is a routing problem present.