Single Area OSPF Cheat Sheet by hoemac16

Router­(co­nfig)# no ip domain­-lookup	disables dns lookup
Router­(co­nfig)# hostname R1	changes hostname
R1(con­fig)# enable secret class	sets password for privileged EXEC
R1(con­fig)# line console 0	changes to line config­uration mode
R1(con­fig­-line)# logging synchr­onous	configures logging synchr­onous (no messages interrupt input)
R1(con­fig­-line)# password cisco	sets console password (also for vty)
R1(con­fig­-line)# login	enables login (also for vty)
R1# copy run start	copies the runnin­g-c­onf­igu­ration to the startu­p-c­onf­igr­ation

Router# show ip route	displays ip routing table
Router# show ip protocols	shows a summary of configured routing protocol inform­ation
Router# show ip ospf	displays general inform­ation of OSPF
Router# show ip ospf interface	displays OSPF inform­ation for the interfaces on the router

R1(con­fig)# router ospf 1	enables OSPF (process id = 1)
R1(con­fig­-ro­uter)# network 192.16­8.1.0 0.0.0.255 area 0	configures a network
R1(con­fig)# interface lo0	configures a loopback interface
R1(con­fig­-if)# ip address 1.1.1.1 255.25­5.2­55.255	sets the ip address of an interface
R1(con­fig­-ro­uter)# router-id 11.11.1­1.11	sets the router id (ospf)
R1(con­fig­-ro­uter)# auto-cost refere­nce­-ba­ndwidth 10000	changes default reference bandwith
R1(con­fig­-if)# bandwidth 128	sets bandwidth of an interface
R1(con­fig­-if)# ip ospf cost 1565	manually sets cost of a link

R2(con­fig­-ro­uter)# no passiv­e-i­nte­rface s0/0/0

removes passive status. router will receive OSPF routing updates.

Router­3#clear ip ospf process

Clears all ospf processes