OSPF uses a router’s Router ID (RID) to identify each router. We see the RID in many OSPF verification commands, so using predictable, known OSPF RID values can help people operate [...]
A router configuration can enable OSPF on an interface directly using the ip ospf interface subcommand. In fact, the configuration is more direct and obvious than the old traditional use of the [...]
When using the OSPF network command, whether single area of multi-area, you have to be careful with the wildcard mask used and which interfaces each network command matches. With multiple areas, [...]
What if your #CCNA exam required you to configure the OSPF network command with a particular style of mask? What if it said “match all addresses in the subnet”, or “match all addresses in the [...]
The OSPF network command can cause a bit of mental trouble for anyone just starting out. The reason: the first two parameters require us to do a little math, compare that result to the router’s [...]
It’s too easy – enabling OSPF per interface rather than using the old IOS network command. In some ways, we may not trust that it’s that easy. So get some practice with today’s lab, a nice clean [...]
From the first days of OSPF in Cisco routers, OSPF configuration has included a network command. The network command enables OSPF on that router’s interfaces, but it uses indirect logic. In fact, [...]
This latest OSPF Enabler exercise asked you to configure four routers in a three-area design. As usual, the exercise asks for different styles of OSPFv2 network commands, for no other reason than [...]
In this latest OSPF Enabler exercise, you’ll configure a network of four routers with three areas. As always, the idea is simple: In one exercise, you’ll get to configure about 10 different [...]
This latest OSPF Enabler exercise asked you to configure four routers in a two-area design. As usual, the exercise asks for different styles of OSPFv2 network commands, for no other reason than [...]
Time for another OSPF Enabler exercise. The idea is simple: In one exercise, you’ll get to configure about 10 different OSPFv2 network commands, with different requirements for each. Just getting [...]
The first OSPF Enabler exercise asked you to configure three routers, specifically to add the OSPFv2 network commands. This post lists the answers – simple enough.
Have you mastered how to configure OSPFv2 yet? If not, look at this exercise that sets up a series of problems for you. In one exercise, you’ll get to choose how to configure about 10 [...]
As with all these #CCNA config museum pieces, the goal is to let you select some practice exercises to get in more reps and make configuration automatic. Today’s post shows the answers; useful [...]
Let’s now do another quick #CCENT and #CCNA practice: Add OSPF configuration, single area. Simple rules, quick review. It uses the same design as in another recent config museum piece as [...]
The previous post changed the OSPF Hello interval (timer) on a WAN serial link. What’s that do to the output of various OSPF commands in our familiar router triangle? What happens to show ip ospf [...]
For this final variation of a #CCNA Simlet question in this series, consider what happens when one OSPF neighbor changes its OSPF Hello interval. Based on what you expect to change, what show [...]