A script that pings a host and for any timeouts, prints the ICMP sequence number and date

check_ping_misses.sh

#!/usr/bin/env bash

# Ping a host and for any timeouts, print the ICMP sequence number and date

set -eEfuo pipefail
IFS=$'\n'

declare -i ICMP_SEQ ICMP_TIMEOUT_IN_SECONDS=1
TARGET_IP=${1}
shift

ping "${TARGET_IP}" -D -n -O -W "${ICMP_TIMEOUT_IN_SECONDS}" |
  {
    # Strip ping header
    read -r

    while read -r ICMP_REQUEST; do
      [[ ${ICMP_REQUEST} =~ ^\[([[:digit:].]+)\].*icmp_seq=([[:digit:]]+) ]]
      ICMP_TIMESTAMP=${BASH_REMATCH[1]}
      ICMP_SEQ=${BASH_REMATCH[2]}

      if [[ ! ${ICMP_REQUEST} =~ \
        "bytes from ${TARGET_IP}: icmp_seq="("${ICMP_SEQ}") ]]; then
        echo \
          "Missed ICMP request ${ICMP_SEQ} at $(date -d @"${ICMP_TIMESTAMP}")!"
      fi
    done
  }