Highest Local Preference (LOCAL_PREF)
The BGP LOCAL_PREF PA allows routers in an AS with multiple exit points to choose which exit point is used to reach a particular NLRI. To do so, the router that is the desired exit point sets the LOCAL_PREF for its eBGP route for that NLRI to a relatively high value, then advertises that route via iBGP. The other routers in the same AS can learn of multiple routes to reach the NLRI, but they will choose the route with the higher LOCAL_PREF as the best route. Table 13-11 summ..
OSPF develops neighbor relationships with routers on the same link by exchanging hello messages (sometimes shortened to hellos). Upon initial exchange of hello messages, the routers add each other to their respective neighbor tables. A neighbor table is a list of connected OSPF speakers (devices running OSPF). OSPF speakers send multicast hellos with destination address 224.0.0.5 on all OSPF-enabled interfaces. OSPF sends out hello packets every 10 seconds on a broadcast link..
Finding Subnet Numbers and Valid Range of IP Addresses—Binary
When examining an IP address and mask, the process of finding the subnet number, the broadcast address, and the range of valid IP addresses is as fundamental to networking as is addition and subtraction for advanced math. Possibly more so for the CCIE Routing and Switching lab exam, mastery of the math behind subnetting, which is the same basic math behind route summarization and filtering, will improve your speed completing complex configurations on the exam. The range of v..
DEC's proprietary networking solution was introduced in 1976. It enjoyed fairly widespread deployment and underwent three revisions, which added scalability and host support as well as SNA gatewaying. This culminated in the release of DEC Network Architecture Phase IV (DNA IV) in 1982. DNA IV features a well-organized network-addressing hierarchy and a peer-to-peer networking philosophy similar in many ways to IP. Indeed, many of the large U.S. federal networks (notably ESNet..
Use the logging buffered configuration command to enable the local storage of router log messages: Router#configure terminal Enter configuration commands, one per line. End with CNTL/Z. Router(config)#logging buffered informational Router(config)#end Router# This feature causes the router to store all log messages to a revolving buffer called the logging buffer. Many network administrators find it convenient and useful to keep detailed router logs on the router itself..
