add check if target is reachable

app.sh

@@ -62,6 +62,8 @@ while true ; do
       echo "Error: can not export $FQDN config"
       exit 2
     fi
+    # check if target is reachable
+    if ping -c1 -W1 "${FQDN}" > /dev/null; then
       echo "export $FQDN config..."
       ssh -n -o StrictHostKeyChecking=no -i "$SSH_KEY_PATH" "${USERNAME}@${FQDN}" "/export show-sensitive" > "config_${FQDN}.rsc" 2> /dev/null
       # entferne Datumszeile
@@ -69,6 +71,9 @@ while true ; do
       git add "config_${FQDN}.rsc"
       echo "commit config for ${FQDN} ..."
       git commit -m "update config_${FQDN}" --quiet > /dev/null
+    else
+      echo "${FQDN} not reachable!"
+    fi
   done <<< "$DEVICES"
 
   echo "push config(s)..."