Skip to content

Instantly share code, notes, and snippets.

@Tras2

Tras2/cloudflare-ddns-update.sh

Last active February 26, 2025 19:57
Download ZIP

Revisions

  1. Tras2 revised this gist Jul 17, 2018. 1 changed file with 7 additions and 0 deletions.
    7 changes: 7 additions & 0 deletions cloudflare-ddns-update.sh
    View file
    Original file line number Diff line number Diff line change
    @@ -23,6 +23,13 @@ ip=$(curl -s -X GET https://checkip.amazonaws.com)

    echo "Current IP is $ip"

    if host $dnsrecord 1.1.1.1 | grep "has address" | grep "$ip"; then
    echo "$dnsrecord is currently set to $ip; no changes needed"
    exit
    fi

    # if here, the dns record needs updating

    # get the zone id for the requested zone
    zoneid=$(curl -s -X GET "https://api.cloudflare.com/client/v4/zones?name=$zone&status=active" \
    -H "X-Auth-Email: $cloudflare_auth_email" \
  2. Tras2 created this gist Jul 17, 2018.
    47 changes: 47 additions & 0 deletions cloudflare-ddns-update.sh
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,47 @@
    #!/bin/bash

    # A bash script to update a Cloudflare DNS A record with the external IP of the source machine
    # Used to provide DDNS service for my home
    # Needs the DNS record pre-creating on Cloudflare

    # Proxy - uncomment and provide details if using a proxy
    #export https_proxy=http://<proxyuser>:<proxypassword>@<proxyip>:<proxyport>

    # Cloudflare zone is the zone which holds the record
    zone=example.com
    # dnsrecord is the A record which will be updated
    dnsrecord=www.example.com

    ## Cloudflare authentication details
    ## keep these private
    cloudflare_auth_email=me@cloudflare.com
    cloudflare_auth_key=1234567890abcdef1234567890abcdef


    # Get the current external IP address
    ip=$(curl -s -X GET https://checkip.amazonaws.com)

    echo "Current IP is $ip"

    # get the zone id for the requested zone
    zoneid=$(curl -s -X GET "https://api.cloudflare.com/client/v4/zones?name=$zone&status=active" \
    -H "X-Auth-Email: $cloudflare_auth_email" \
    -H "X-Auth-Key: $cloudflare_auth_key" \
    -H "Content-Type: application/json" | jq -r '{"result"}[] | .[0] | .id')

    echo "Zoneid for $zone is $zoneid"

    # get the dns record id
    dnsrecordid=$(curl -s -X GET "https://api.cloudflare.com/client/v4/zones/$zoneid/dns_records?type=A&name=$dnsrecord" \
    -H "X-Auth-Email: $cloudflare_auth_email" \
    -H "X-Auth-Key: $cloudflare_auth_key" \
    -H "Content-Type: application/json" | jq -r '{"result"}[] | .[0] | .id')

    echo "DNSrecordid for $dnsrecord is $dnsrecordid"

    # update the record
    curl -s -X PUT "https://api.cloudflare.com/client/v4/zones/$zoneid/dns_records/$dnsrecordid" \
    -H "X-Auth-Email: $cloudflare_auth_email" \
    -H "X-Auth-Key: $cloudflare_auth_key" \
    -H "Content-Type: application/json" \
    --data "{\"type\":\"A\",\"name\":\"$dnsrecord\",\"content\":\"$ip\",\"ttl\":1,\"proxied\":false}" | jq