Merge pull request #298 from senarvi/duckdns-random-delay

Add a random delay before duckdns request

Author: Slyke

docs/Accessing-your-Device-from-the-internet.md

@@ -17,7 +17,7 @@ first test the script to make sure it works `sudo ~/IOTstack/duck/duck.sh` then
 Create a cron job by running the following command `crontab -e`
 
 You will be asked to use an editor option 1 for nano should be fine
-paste the following in the editor `*/5 * * * * sudo ~/IOTstack/duck/duck.sh >/dev/null 2>&1` then ctrl+s and ctrl+x to save
+paste the following in the editor `*/5 * * * * ~/IOTstack/duck/duck.sh` then ctrl+s and ctrl+x to save
 
 Your Public IP should be updated every five minutes
 

duck/duck.sh

@@ -3,4 +3,8 @@
 DOMAINS="YOUR_DOMAINS"
 # Your DuckDNS Token
 DUCKDNS_TOKEN="YOUR_DUCKDNS_TOKEN"
-curl -k -o /var/log/duck.log "https://www.duckdns.org/update?domains=${DOMAINS}&token=${DUCKDNS_TOKEN}&ip="
+
+# A random delay to avoid every client contacting the duckdns server at the same moment
+sleep $((RANDOM % 60))
+# Request duckdns to update your domain name with your public IP address
+curl --silent --max-time 10 --output /dev/null "https://www.duckdns.org/update?domains=${DOMAINS}&token=${DUCKDNS_TOKEN}&ip="