Cisco CCNA Routing and Switching ICND2 200-101 Official Cert Guide

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Many people tend to get a little intimidated by OSPF LSAs when first learning about them. The output of the show ip ospf database command—a command that lists a summary of the output—is pretty long. Commands that look at specific LSAs list a lot more information. The details appear to be in some kind of code, using lots of numbers. It can seem like a bit of a mess.

However, if you examine LSAs while thinking about OSPF areas, and area design, some of the most common LSA types will make a lot more sense. For instance, think about the LSDB in one area, like the example shown in Figure 8-8. The topology details included routers and the links between the routers. As it turns out, OSPF defines the first two types of LSAs ...