Viewing ICMP Statistics and Errors
Page 25-21
Address Mask Messages
The number of Address Mask Reply messages that were sent/received by this switch in an
attempt to determine the subnet mask for a network.
Address Mask Reply Messages
The number of Address Mask Reply messages that were sent/received by this switch.
Errors
The number of ICMP messages this switch sent/received but was unable to process because
something was wrong (for example, a checksum failure).
Destination Unreachable Msgs
The number of ICMP “destination unreachable” messages that were sent/received. These
occur when the gateway is unable to route a datagram to its destination.
Time Exceeded Msgs
The number of “time exceeded” messages that were sent/received. These occur when a
packet is dropped because the Time-to-Live counter reaches zero. When a large number of
these messages are encountered this is a symptom that packets are looping, that congestion is
severe, or that the Time-to-Live counter is set too low. These messages also occur when all
the fragments trying to be reassembled don‘t arrive before the reassembly timer expires.
Parameter Problems
The number of messages sent/received which indicate that an illegal value has been detected
in a header field. These messages can indicate a problem in the sending host’s IP software or
possibly in the gateway’s software.
Source Quenches
The number of messages sent/received which tell a host that is sending too many packets. A
host should attempt to reduce its transmissions upon receiving these messages.