Day 13 - Single Area OSPF Implementation Flashcards
What is the first command to enter when enabling OSPF on a router with a process ID of 10?
router ospf 10
What is the range of numbers that an OSPF process ID can be?
0 - 65535
True or False:
The OSPF process ID has to match other OSPF routers to establish adjacencies with their neighbors?
False
This differs from EIGRP where the process ID and AS number must match to form adjacencies
Put these steps in order of how a Cisco router chooses its router ID
- If the router ID isn’t configured, the router chooses the highest IP address of any of its loopback interfaces
- The router uses the IP address configured with the OSPF router-id command
- If no loopback interfaces are configured, the router chooses the highest active IP address of any of its physical interfaces
2
1
3
What commands would you use to verify or view the Router ID?
show ip ospf int
show ip protocols
show ip ospf
Configure a Router ID based on this topology using 1.1.1.1, 2.2.2.2 and 3.3.3.3 matching up with the routers while using a process ID of 10
R1
router ospf 10
router-id 1.1.1.1
R2
router ospf 10
router-id 2.2.2.2
R3
router ospf 10
router-id 3.3.3.3
True or False:
You should configure the router ID manually before invoking OSPF
True
If you do not configure manual router IDs and then want to after enabling OSPF, what command can you use to reset OSPF to pick up the changes?
clear ip ospf process
An __________ __________ is a group of routers that share link-state information
OSPF Area
All OSPF routers in the same area must have the same __________ __________ __________ in their link-state databases
Link state information
In the topology shown for R1, instead of targeting a network address, what commands could you use to directly target the interfaces 172.16.1.1, 172.16.3.1 and 192.168.10.5 and enable them for OSPF with a process ID of 10?
router ospf 10
network 172.16.1.1 0.0.0.0 area 0
network 172.16.3.1 0.0.0.0 area 0
network 192.168.10.5 0.0.0.0 area 0
In the topology shown for R2, in targeting network addresses, what commands could you use to directly target the networks of 172.16.2.0. 172.16.3.0 and 192.168.10.8 and enable them for OSPF with a process ID of 10?
router ospf 10
network 172.16.2.0 0.0.0.255 area 0
network 172.16.3.0 0.0.0.3 area 0
network 192.168.10.8 0.0.0.3 area 0
In the topology shown for R3, in targeting network addresses, what commands could you use to directly target the networks 192.168.1.0, 192.168.10.4 and 192.168.10.8 and enable them for OSPF with a process ID of 10?
router ospf 10
network 192.168.1.0 0.0.0.255 area 0
network 192.168.10.4 0.0.0.3 area 0
network 192.168.10.8 0.0.0.3 area 0
By default, OSPF __________ are forwarded out all OSPF-enabled interfaces
Messages
Which interfaces do not need to be privy to the OSPF process?
Gi0/0 on every router
What commands would you use to make Gi0/0 a passive interface on R1, R2 and R3?
router ospf 10
passive-interface gi0/0
What the is default OSPF cost value for a 10 Gig interface?
1
What the is default OSPF cost value for a 1 Gig interface?
1
What the is default OSPF cost value for a 100Mbps (FA) interface?
1
What the is default OSPF cost value for a 10Mbps (Ethernet) interface?
10
What the is default OSPF cost value for a T1 interface?
64
As a matter of policy you should change the __________ __________ to accommodate networks with links faster than 100Mbps (100,000,000 bps)
Reference bandwidth
What is the command to change the reference bandwidth within the OSPF router?
router ospf 10
auto-cost reference bandwidth {Mbps}
What is the maximum OSPF cost for a Cisco router interface?
65535
What is the most advantageous command you could use to alter the cost of an OSPF interface?
ip ospf cost {cost}
What 3 generic commands could you use to verify OSPF as well as any other routing protocol?
show ip int brief
show ip route
show ip protocols
What command would you use to verify neighbor adjacency in OSPF?
show ip ospf neighbor
What command is the quickest way to verify OSPF interface settings such as process ID, area, ip addresses, cost, neighbors, etc
show ip ospf int brief
