test# config t
Enter configuration commands, one per line.  End with CNTL/Z.
test(config)# ip default-g ?
  A.B.C.D  IP address of default gateway

test(config)# ip default-g 1.2.3.4
test(config)# cdp ?
  advertise-v2      CDP sends version-2 advertisements
  holdtime          Specify the holdtime (in sec) to be sent in packets
  log               Log messages generated by CDP
  run               Enable CDP
  source-interface  Insert the interface's IP in all CDP packets
  timer             Specify rate (in sec) at which CDP packets are sent

test(config)# cdp run

test(config)# cdp ?
  advertise-v2      CDP sends version-2 advertisements
  holdtime          Specify the holdtime (in sec) to be sent in packets
  log               Log messages generated by CDP
  run               Enable CDP
  source-interface  Insert the interface's IP in all CDP packets
  timer             Specify rate (in sec) at which CDP packets are sent

test(config)# cdp timer ?
  <5-254>  Rate at which CDP packets are sent (in  sec)

test(config)# cdp timer 10
test(config)# cdp holdtime ?
  <10-255>  Length  of time  (in sec) that receiver must keep this packet

test(config)# cdp holdtime 20
test(config)# int fa0/0
test(config-if)# cdp ?
  enable  Enable CDP on interface
  log     Log messages generated by CDP

test(config-if)# cdp enable
test(config-if)# exit