User manual

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show icmp counters
Shows Input and Output Counters for ICMP. Two types of ICMP messages -
error and query messages - are sent to syslog hosts.
ICMP COUNTERS
INPUT COUNTERS
• Messages
- ICMP packets received
• Errors
- ICMP packets received with errors
• Destination Unreachable
- sum of ICMP messages received when a
router cannot forward a packet to its specified destination
• Time Exceeded
- sum of ICMP messages generated by a router when
time has exceeded or a timeout has occurred while waiting for a packet
segment
• Parameter Problems
- sum of ICMP messages generated by a router
when it encounters an error
• Source Quench
- sum of ICMP messages informing a host it should slow
data transmission to ease congestion
• Redirects
- sum of ICMP messages concerning a router advertising a
host of a better next hop
• Echos
- sum of ICMP request messages received, signifying transport
system success
• Echo Replies
- sum of ICMP reply messages received, indicating
transport system success
• Timestamps
- sum of ICMP request messages received seeking time from
another machine for clock synchronization and estimated transit time
purposes
• Timestamp Replies
- sum of ICMP timestamp reply messages
• Address Masks
- sum of ICMP Address Mask Reply messages
• Address Mask Replies
- sum of ICMP request messages concerning a
host’s ability to gather network information
• Advertise
-
• Solicit
-
OUTPUT COUNTERS
• Messages
- total of ICMP messages transmitted
• Errors
- ICMP packets transmitted with errors