diff --git a/Dockerfile b/Dockerfile
index 86b73238..c586dd49 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -32,7 +32,7 @@ FROM $node_image AS production
 ENV NODE_ENV=production
 RUN npm install --global pm2; \
     apt update; \
-    apt install -y nginx openssl curl
+    apt install -y nginx openssl curl ncat
 
 RUN rm /etc/nginx/sites-enabled/default; \
     ln -s /app/docker-assets/siren-http.conf /etc/nginx/conf.d/siren-http.conf
diff --git a/docker-assets/docker-entrypoint.sh b/docker-assets/docker-entrypoint.sh
index be1fc7bc..51610d80 100755
--- a/docker-assets/docker-entrypoint.sh
+++ b/docker-assets/docker-entrypoint.sh
@@ -15,7 +15,11 @@ set +a
 # if bn/vc api unreachable, print message and exit
 tests="${BEACON_URL} ${VALIDATOR_URL}"
 for test in $tests; do 
-  nc -z "${test#*//}"
+  host="${test#*//}"
+  host="${host%%:*}"
+  port="${test##*:}"
+  nc -z $host $port
+
   if [ $? -eq 1 ]; then
     printf "${test} unreachable, check settings and connection\n"
     fail=true