From b181682b20d11c1b9da83f2f19d2b3742bda86f1 Mon Sep 17 00:00:00 2001
From: "LORENZO\\pacio" <paciotti@poloinformatico.it>
Date: Mon, 14 Jul 2025 17:56:31 +0200
Subject: [PATCH] .

---
 Dockerfile         | 11 +++++++++++
 check.sh           | 34 ++++++++++++++++++++++++++++++++++
 docker-compose.yml |  9 +++++++++
 3 files changed, 54 insertions(+)
 create mode 100644 Dockerfile
 create mode 100644 check.sh
 create mode 100644 docker-compose.yml

diff --git a/Dockerfile b/Dockerfile
new file mode 100644
index 0000000..90fe002
--- /dev/null
+++ b/Dockerfile
@@ -0,0 +1,11 @@
+FROM alpine:latest
+
+RUN apk add --no-cache iputils coreutils tzdata
+
+ENV TZ=Europe/Rome
+
+WORKDIR /app
+COPY check.sh .
+RUN chmod +x check.sh
+
+CMD ["./check.sh"]
diff --git a/check.sh b/check.sh
new file mode 100644
index 0000000..150b911
--- /dev/null
+++ b/check.sh
@@ -0,0 +1,34 @@
+#!/bin/sh
+
+HOST="${HOST_TO_CHECK:-example.com}"
+INTERVAL="${INTERVAL_SECONDS:-300}"
+LOGFILE="/logs/${HOST}.log"
+
+mkdir -p /logs
+
+echo "Monitoring $HOST every $INTERVAL seconds..."
+
+while true; do
+  OUTPUT=$(ping -c 1 -W 2 "$HOST" 2>&1)
+  EXIT_CODE=$?
+
+  if [ $EXIT_CODE -ne 0 ]; then
+    TIMESTAMP=$(date '+%Y-%m-%d %H:%M:%S')
+
+    if echo "$OUTPUT" | grep -q "bad address"; then
+      REASON="DNS resolution failed"
+    elif echo "$OUTPUT" | grep -q "Network is unreachable"; then
+      REASON="No route to network"
+    elif echo "$OUTPUT" | grep -q "ping: permission denied"; then
+      REASON="ICMP not permitted (try running as root or with CAP_NET_RAW)"
+    elif echo "$OUTPUT" | grep -q "100% packet loss"; then
+      REASON="Timed out (no response)"
+    else
+      REASON="Unknown error: $OUTPUT"
+    fi
+
+    echo "[$TIMESTAMP] Host unreachable: $HOST — Reason: $REASON" | tee -a "$LOGFILE"
+  fi
+
+  sleep "$INTERVAL"
+done
diff --git a/docker-compose.yml b/docker-compose.yml
new file mode 100644
index 0000000..be50d6c
--- /dev/null
+++ b/docker-compose.yml
@@ -0,0 +1,9 @@
+services:
+  host-checker:
+    build: .
+    environment:
+      - HOST_TO_CHECK=psql01.poloinformatico.it
+      - INTERVAL_SECONDS=120
+    volumes:
+      - ./logs:/logs
+    restart: always