This section covers the core OSPF configuration commands, along with the OSPF configuration topics not already covered previously in the chapter. (If you happened to skip the earlier parts of this chapter, planning to review OSPF configuration, make sure to go back and look at the earlier examples in the chapter. These examples cover OSPF stubby area configuration, OSPF network types, plus OSPF neighbor and priority commands.) Example 10-8 shows configuration for the routers..
PIM has two modes of operation—dense mode and sparse mode. Dense mode uses a flood-and-prune mechanism to forward multicast packets. The router assumes that every multicast interface is interested in multicast packets, unless it is told otherwise. The router first forwards multicast packets to all the interfaces. Segments that don't want multicast packets receive prune messages from the neighboring routers, and the branch is pruned. When the router is first configured for ..
Revision Control of IOS Configuration Files
All IOS configuration changes should be recorded and, if possible, a reason for each change should be logged. Such revision control may be achieved with a commercial package, such as CiscoWorks; or with public domain software, such as RCS. In the latter case, good results can be achieved simply by following these guidelines: Always write modified router configurations to a tftp server, using a well-known name for each router configuration file. Hav..
Broadcast Suppression: Advanced Traffic Management
Some members of the Catalyst family support a feature intended to minimize the transfer of broadcast and multicast frames sourced from a port. The broadcast/multicast suppression feature measures the broadcast and multicast traffic coming from a device and restricts the flow of the frames across the Catalyst switch fabric if the amount of the traffic exceeds a configurable threshold. Depending upon your version of Catalyst, you have two methods to measure the broadcast and m..
Controlling Congestion with WRED
The syntax for configuring WRED changed with the introduction of class-based QoS. The old method defined WRED across an entire interface: Router#configure terminal Enter configuration commands, one per line. End with CNTL/Z. Router(config)#interface HSSI0/0 Router(config-if)#random-detect Router(config-if)#random-detect precedence 0 10 20 10 Router(config-if)#random-detect precedence 1 12 20 10 Router(config-if)#random-detect precedence 2 15 25 15 Router(config-if)#ran..
