Problem statement
At first glance, it looks safe to use the loopback address 127.0.0.1 for MikroTik watchdog ping.
The assumption is simple: the router can always ping itself, so it should never trigger a reboot.
I just couldn’t find in the documentation how to disable this ping correctly ( if configured once ), and I think, why not use 127.0.0.1 … after all, it’s always available for pinging.
[user@mikrotik] /system/watchdog> /system/watchdog/print
watch-address: 127.0.0.1
watchdog-timer: no
ping-start-after-boot: 5m
ping-timeout: 5m
automatic-supout: no
auto-send-supout: no
However, this is not the case in MikroTik and you will see unexpected watchdog reboots with logs like:
[user@mikrotik] /system/watchdog> /log/print
2025-10-03 13:08:55 system,error,critical router was rebooted without proper shutdown by watchdog timer
2025-10-03 13:08:55 interface,info lo link up

Solution: Using Watchdog with 0.0.0.0
[user@mikrotik] > /system/watchdog/set watch-address=0.0.0.0
[user@mikrotik] > /system/watchdog/print
watch-address: none
watchdog-timer: no
ping-start-after-boot: 5m
ping-timeout: 5m
automatic-supout: no
auto-send-supout: no
Does not work
unset- not available herereset- not available herewatch-address=""also does not work
Version
[user@mikrotik] > system/resource/print
version: 7.20 (stable)
build-time: 2025-09-29 09:33:57
architecture-name: arm
board-name: wAP R ac
platform: MikroTik