ICMP Errors

Type

Message

Code values

3

Destination Unreachable

0 = Net unreachable

1 = Host unreachable

2 = Protocol unreachable

3 = Port unreachable

4 = Fragmentation needed (DF set)

5 = Source route failed

6 = Destination network unknown

7 = Destination host unknown

9 = Network administratively prohibited

10 = Host administratively prohibited

13 = Communication administratively prohibited

4

Source Quench (deprecated)

Always 0

5

Redirect

0 = Redirect datagram for the network

1 = Redirect datagram for the host

2 = Redirect for TOS and network

3 = Redirect for TOS and host

11

Time Exceeded

0 = TTL exceeded in transit

1 = Fragment reassembly time exceeded

12

Parameter Problem

0 = Pointer indicates the error

1 = Missing required option

2 = Bad length