#!/bin/bash
# Timestamped liveness log for the Management VLAN during the bond0 -> bond0.1 move.
#
# The question this answers is not "did it work" but "for how long was it not
# working, and what held the VIP while it was not". Both are invisible after the
# fact: VRRP reconverges and leaves no trace of who was master during the gap.
#
#   ./vlan1-move-monitor.sh > /tmp/move.log &
# Columns: time  VIP-ping  R1-ping  R2-ping  VIP-mac
VIP="${VIP:-172.31.1.1}"; R1="${R1:-172.31.1.252}"; R2="${R2:-172.31.1.253}"
p() { ping -c1 -W1 -n "$1" >/dev/null 2>&1 && echo up || echo DOWN; }
while :; do
  mac="$(ip neigh show "$VIP" 2>/dev/null | awk '{for(i=1;i<=NF;i++) if($i=="lladdr") print $(i+1)}')"
  printf '%s  vip=%-4s r1=%-4s r2=%-4s vipmac=%s\n' \
    "$(date +%H:%M:%S)" "$(p "$VIP")" "$(p "$R1")" "$(p "$R2")" "${mac:-none}"
  sleep 1
done