diff --git a/mailcow/src/mailcow-dockerized/data/Dockerfiles/watchdog/watchdog.sh b/mailcow/src/mailcow-dockerized/data/Dockerfiles/watchdog/watchdog.sh
index 428aed6..4013cb4 100755
--- a/mailcow/src/mailcow-dockerized/data/Dockerfiles/watchdog/watchdog.sh
+++ b/mailcow/src/mailcow-dockerized/data/Dockerfiles/watchdog/watchdog.sh
@@ -251,7 +251,7 @@
     touch /tmp/unbound-mailcow; echo "$(tail -50 /tmp/unbound-mailcow)" > /tmp/unbound-mailcow
     host_ip=$(get_container_ip unbound-mailcow)
     err_c_cur=${err_count}
-    /usr/lib/nagios/plugins/check_dns -s ${host_ip} -H stackoverflow.com 2>> /tmp/unbound-mailcow 1>&2; err_count=$(( ${err_count} + $? ))
+    /usr/bin/nslookup -sil stackoverflow.com "${host_ip}" 2>> /tmp/unbound-mailcow 1>&2; err_count=$(( ${err_count} + $? ))
     DNSSEC=$(dig com +dnssec "@${host_ip}" | egrep 'flags:.+ad')
     if [[ -z ${DNSSEC} ]]; then
       echo "DNSSEC failure" 2>> /tmp/unbound-mailcow 1>&2