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@Firsh
Last active February 21, 2025 13:51
Cloudflare as Dynamic DNS
#!/bin/bash
# Cloudflare as Dynamic DNS
# From: https://letswp.io/cloudflare-as-dynamic-dns-raspberry-pi/
# Based on: https://gist.github.com/benkulbertis/fff10759c2391b6618dd/
# Original non-RPi article: https://phillymesh.net/2016/02/23/setting-up-dynamic-dns-for-your-registered-domain-through-cloudflare/
# Update these with real values
auth_email="email@example.com"
auth_key="global_api_key_goes_here"
zone_name="example.com"
record_name="home.example.com"
# Don't touch these
ip=$(curl -s http://ipv4.icanhazip.com)
ip_file="ip.txt"
id_file="cloudflare.ids"
log_file="cloudflare.log"
# Keep files in the same folder when run from cron
current="$(pwd)"
cd "$(dirname "$(readlink -f "$0")")"
log() {
if [ "$1" ]; then
echo -e "[$(date)] - $1" >> $log_file
fi
}
log "Check Initiated"
if [ -f $ip_file ]; then
old_ip=$(cat $ip_file)
if [ $ip == $old_ip ]; then
log "IP has not changed."
exit 0
fi
fi
if [ -f $id_file ] && [ $(wc -l $id_file | cut -d " " -f 1) == 2 ]; then
zone_identifier=$(head -1 $id_file)
record_identifier=$(tail -1 $id_file)
else
zone_identifier=$(curl -s -X GET "https://api.cloudflare.com/client/v4/zones?name=$zone_name" -H "X-Auth-Email: $auth_email" -H "X-Auth-Key: $auth_key" -H "Content-Type: application/json" | grep -Po '(?<="id":")[^"]*' | head -1 )
record_identifier=$(curl -s -X GET "https://api.cloudflare.com/client/v4/zones/$zone_identifier/dns_records?name=$record_name" -H "X-Auth-Email: $auth_email" -H "X-Auth-Key: $auth_key" -H "Content-Type: application/json" | grep -Po '(?<="id":")[^"]*')
echo "$zone_identifier" > $id_file
echo "$record_identifier" >> $id_file
fi
update=$(curl -s -X PUT "https://api.cloudflare.com/client/v4/zones/$zone_identifier/dns_records/$record_identifier" -H "X-Auth-Email: $auth_email" -H "X-Auth-Key: $auth_key" -H "Content-Type: application/json" --data "{\"id\":\"$zone_identifier\",\"type\":\"A\",\"name\":\"$record_name\",\"content\":\"$ip\"}")
if [[ $update == *"\"success\":false"* ]]; then
message="API UPDATE FAILED. DUMPING RESULTS:\n$update"
log "$message"
echo -e "$message"
exit 1
else
message="IP changed to: $ip"
echo "$ip" > $ip_file
log "$message"
echo "$message"
fi
@Australian
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@tarasis I wish i could talk to 'old you' because i am getting that same error. as you.

@Australian
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Getting: API UPDATE FAILED. DUMPING RESULTS: {"success":false,"errors":[{"code":7003,"message":"Could not route to /zones/dns_records, perhaps your object identifier is invalid?"},{"code":7000,"message":"No route for that URI"}],"messages":[],"result":null}

Any idea? It is an account with multiple domains.

Hiya... did you ever get this to work?

@produktive
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I implemented logrotate. This will rotate the log files each day for 7 days before deleting the oldest one. Then you don't have a giant growing log file for eternity. Before running the program:

sudo mkdir /var/log/cloudflare
sudo chown $USER:$USER /var/log/cloudflare/
touch /var/log/cloudflare/cloudflare.log
nano /etc/logrotate.d/cloudflare

Enter in /etc/logrotate.d/cloudflare file:

/var/log/cloudflare/cloudflare.log {
	rotate 7
	daily
}

Save the file. Then change directory back to where this script (lwp-cloudflare-dyndns.sh) is located. For me, ~/cloudflare. Finally:
ln -s cloudflare.log /var/log/cloudflare/cloudflare.log

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