diff --git a/tunnel-checker.sh b/tunnel-checker.sh
new file mode 100755
index 0000000..572c4bb
--- /dev/null
+++ b/tunnel-checker.sh
@@ -0,0 +1,65 @@
+#!/bin/sh
+
+[ -n "$SECRET_KEY" ] || { echo "Please define SECRET_KEY"; exit 1; }
+
+while true
+do
+
+CNT=$(curl -s https://adlin.nemunai.re/api/ips)
+
+
+# Perform checks
+
+echo "${CNT}" | jq -r '. | keys | .[]' - | while read sid
+do
+    IP=$(echo "${CNT}" | jq -r '.["'$sid'"].wg' -)
+    if [ -n "${IP}" ]
+    then
+	echo -ne "\n${sid}: "
+	ping6 -q -c 1 -w 1 "${IP}1" > /dev/null && {
+	    echo -n "PONG "
+	    curl -k -X POST -d '{"token": "'${SECRET_KEY}'"}' -H "X-Forwarded-Proto: https" "https://adlin.nemunai.re/api/students/$sid/pong"
+
+	    # TUTO2 checks
+
+	    # port 80
+	    PAGE=$(curl -f -s "http://[${IP}1]/") &&
+		curl -X POST -d @- "https://adlin.nemunai.re/challenge/100" <<EOF
+{
+  "token": "${SECRET_KEY}",
+  "login": "${sid}",
+  "data": ["$(echo ${PAGE} | sha1sum | cut -d ' ' -f 1)"]
+}
+EOF
+
+	    # port 443
+	    PAGE=$(openssl s_client -host "${IP}1" -port 443 2> /dev/null) &&
+		curl -X POST -d @- "https://adlin.nemunai.re/challenge/101" <<EOF
+{
+  "token": "${SECRET_KEY}",
+  "login": "${sid}",
+  "data": ["$(echo ${PAGE} | sha1sum | cut -d ' ' -f 1)"]
+}
+EOF
+
+	    DDN=$(echo "${CNT}" | jq -r '.["'$sid'"].ddn' -)
+	    if [ -n "${DDN}" ]
+	    then
+		# port 53
+		DIG=$(LD_PRELOAD=/usr/lib/gcc/armv5tel-softfloat-linux-gnueabi/8.2.0/libgcc_s.so.1 kdig +time=1 +noretry +short "@${IP}1" "${DDN}" SOA 2> /dev/null)
+		[ -n "${DIG}" ] &&
+		    curl -X POST -d @- "https://adlin.nemunai.re/challenge/102" <<EOF
+{
+  "token": "${SECRET_KEY}",
+  "login": "${sid}",
+  "data": ["${DIG}"]
+}
+EOF
+	    fi
+	}
+    fi
+done
+
+sleep 5
+
+done