DynamicDNS Route53 Update.

r53DynUp.sh

#!/bin/bash
ZONEID=YOUR_HOSTED_ZONE_ID
export PATH=/bin:/usr/bin:/usr/local/bin

DNS_RECORD="$1"

function digIP () {
	while true; do 
		CURRENT_IP=`dig +short +time=5 "$1"`
		if [ -n "$CURRENT_IP" ]; then 
			echo "$CURRENT_IP";
			return
		else
			sleep 5
		fi
	done
}

function curlIP {
	ENDPOINT[0]="https://api.ipify.org"
	ENDPOINT[1]="http://ifconfig.co/"
	ENDPOINT[2]="http://ifconfig.me/"
	i=0
	while true; do 
		CURLED_IP=`curl -s ${ENDPOINT[$i]} --connect-timeout 10 -4`
		if [ -n "$CURLED_IP" ]; then 
			echo "$CURLED_IP";
			return
		else
			i=$i+1
			sleep 5
		fi
	done
}

CURRENT_IP=`digIP "${DNS_RECORD}"`
CURLED_IP=`curlIP`

if [ "$CURRENT_IP" == "$CURLED_IP" ]; then
	echo "[`date`] A Record ${CURRENT_IP} and detected IP ${CURLED_IP} still matches"
	exit 0
else
	echo "[`date`] The Current Record of ${CURRENT_IP} does not match detected IP ${CURLED_IP}"
fi

JSON='{
    "HostedZoneId": "",
    "ChangeBatch": {
        "Comment": "Update IP",
        "Changes": [
            {
                "Action": "UPSERT",
                "ResourceRecordSet": {
                    "Name": "'${DNS_RECORD}'",
                    "Type": "A",
                    "TTL": 60,
                    "ResourceRecords": [
                        {
                            "Value": "'${CURLED_IP}'"
                        }
                    ]
                }
            }
        ]
    }
}'
echo $JSON > /tmp/ipUpdate.json

while true; do
	aws route53  change-resource-record-sets --hosted-zone-id ${ZONEID} --cli-input-json file:///tmp/ipUpdate.json &> /tmp/R53Update.log
	if [ $? -eq 0 ]; then
		echo "Route53 Update Successfull"
		exit 0
	else
		echo "Route 53 Update not successful"
		sleep 5
	fi
done