Filtering Routes Using the distribute-list Command
For RIP and EIGRP, the distribute-list command can be used to filter incoming and outgoing routing updates. The process is straightforward, with the distribute-list command referring to ACLs or prefix lists. With OSPF, the distribute-list command filters what ends up in the IP routing table, and on only the router on which the distribute-list command is configured. NOTE The distribute-list command, when used for route distribution between OSPF and other routing protocols, ..
PIM sparse mode works the opposite way of dense mode. PIM dense mode assumes that all the multicast interfaces are interested in multicast packets, unless being told otherwise. In PIM sparse mode, the router assumes that none of the multicast inter-faces is interested in receiving multicast packets, unless a PIM join message is received on the interface. PIM sparse mode is more scalable than PIM dense mode, but the concept is more complex. PIM sparse mode uses the concept of ..
Case Study: Troubleshooting BGP Neighbor Relationships
Because BGP is designed as an EGP, rather than an IGP, BGP neighbor relationships are not complex. The primary thing to keep in mind is that all communications between BGP peers are based on Transmission Control Protocol (TCP). Therefore, an IP connection must be in place between the peers before a relationship can be established. Look at the network in Figure 6-1, which has only three routers, to see the problems that are possible. Figure 6-1. Simple Network with BGP Peers ..
The initial Layer 3 switching engine for the Catalyst 6000 family consisted of the Multi-layer Switch Model (MSM). Based on Catalyst 8510 technology, the MSM provides a router-on-a-stick configuration integrated into the Catalyst 6000 chassis. Therefore, the MSM brings the power of the 8510 to the Catalyst 6000 family (namely IP and IPX routing at approximately 5 million packets per second [mpps]). Note The MSM contains a faster CPU that is currently used in the 8510. From..
You can insert a single entry into an existing ACL by specifying a sequence number, as follows: Router2#configure terminal Enter configuration commands, one per line. End with CNTL/Z.Router2(config)#ip access-list extended OREILLY Router2(config-ext-nacl)#12 permit tcp any host 172.25.100.100 eq 20Router2(config-ext-nacl)#endRouter2# The following commands show how t..
