Alcatel-Lucent 7750 SR OS - page 256

Configuration Commands
Page 256 7750 SR OS Router Configuration Guide
With each consecutive attempt to send an ICMP echo request message, the timeout timer is loaded
with the timeout value. The timer decrements until:
• An internal error occurs preventing message sending (request unsuccessful).
• An internal error occurs preventing message reply receiving (request unsuccessful).
• A required route table entry does not exist to reach the IP address (request unsuccessful).
• A required ARP entry does not exist and ARP request timed out (request unsuccessful).
• A valid reply is received (request successful).
Note that it is possible for a required ARP request to succeed or timeout after the message timeout
timer expires. In this case, the message request is unsuccessful.
If an ICMP echo reply message is not received prior to the timeout period for a given ICMP echo
request, that request is considered to be dropped and increments the consecutive message drop
counter for the priority event.
If an ICMP echo reply message with the same sequence number as an outstanding ICMP echo
request message is received prior to that message timing out, the request is considered successful.
The consecutive message drop counter is cleared and the request message no longer is outstanding.
If an ICMP Echo Reply message with a sequence number equal to an ICMP echo request sequence
number that had previously timed out is received, that reply is silently discarded while incrementing
the priority event reply discard counter.
The no form of the command reverts to the default value.
Default 1 — 1 second timeout to receive an ICMP echo reply in response to an ICMP echo request.
Parameters seconds — The number of seconds before an ICMP echo request message is timed out. Once a
message is timed out, a reply with the same identifier and sequence number is discarded.
Values 1 — 60