navilg / namecheap-ddns-docker

Dynamic DNS client for namecheap

Namecheap DDNS docker client

When to use ?

If your server do not have static IP, i.e. When Public IP of your server / router keep changing, This will automatically update new IP to Namecheap record.

Why to use it ?

• Easy to setup

• Lightweight

• No cronjob configuration required

• Logs for visibility

• Open source

How to use it

• Change nameserver of you domain to BasicDNS or PremiumDNS or FreeDNS. Namecheap Account -> Domain List -> Manage -> Domain -> NAMESERVERS -> Choose BasicDNS from dropdown

• Enable Dynamic DNS for your domain from Namecheap. Namecheap Account -> Domain List -> Manage -> Advanced DNS -> Dynamic DNS -> Toggle Status

• Copy the Dynamic DNS password which is generated after enabling Dynamic DNS. Keep it safe and handy.

• Add a record of type A + Dynamic DNS with required host name.

• Install docker on server.

• Run below command

Suppose, You need DDNS for server.example.com

docker run --name server.example.com -d --restart unless-stopped -e NC_HOST='server' -e NC_DOMAIN='example.com' -e NC_PASS='DynamicDDNSPa2w0rd' linuxshots/namecheap-ddns

Here, NC_HOST is host name added in Namecheap record.

NC_DOMAIN is your domain name.

NC_PASS is your Dynamic DDNS password which is generated from Namecheap.

• Check the log

docker logs server.example.com

• To stop, start and remove DDNS.

docker stop server.example.com # To stop
docker start server.example.com # To start after its stopped
docker rm server.example.com -f # To remove

Build your own image

To build your own image

• Clone this repo

• Run docker build

# Replace OS and ARCH values with valid values of GOlang environment variables GOOS and GOARCH.
docker build --build-arg VERSION=1.0.0 -t linuxshots/namecheap-ddns . 

NOTE: This sets the TTL to Automatic i.e. 30 minutes. Currently, There is no way provided by Namecheap to set custom TTL in Dynamic DDNS.

namecheap-ddns-docker's Issues

Timeout the pubIp env variable set in container

Currently when IP address is set in namecheap, ncddns sets an env variable in current container so that it can compare the next time with current public IP. It prints the message "DNS record is same as current IP" if current public IP and env variable set is same.

This may not work if someone changes the IP address of a dns from namecheap dashboard unless container is restarted again. To avoid this, We can have a timeout set for env variable set, after which it should be wiped out so that fresh attempt to add ip address is made by ncddns.

If pubIp is empty, it updates ip with private ip in dns record

Wrong requests contain error message and return status code 200

I've noticed the following code:

// req.Header.Add("Accept", "text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,*/*")
	// req.Header.Add("Accept-Encoding", "gzip, deflate, br")
	// req.Header.Add("Connection", "keep-alive")

	response, err := apiclient.Do(req)
	if err != nil {
		// fmt.Println(2, err.Error())
		return err
	}

	defer response.Body.Close()

	if response.StatusCode != 200 {
		return &CustomError{ErrorCode: response.StatusCode, Err: errors.New(response.Status)}
	}

It expects to have a HTTP status different than 200 when having an error. Yet, that's not the case. They are sending a XML payload with the error under 200.

<?xml version="1.0" encoding="utf-16"?>
<interface-response>
  <Command>SETDNSHOST</Command>
  <Language>eng</Language>
  <ErrCount>1</ErrCount>
  <errors>
    <Err1>Passwords do not match</Err1>
  </errors>
  <ResponseCount>1</ResponseCount>
  <responses>
    <response>
      <Description>Passwords do not match</Description>
      <ResponseNumber>304156</ResponseNumber>
      <ResponseString>Validation error; invalid ; password</ResponseString>
    </response>
  </responses>
  <Done>true</Done>
  <debug><![CDATA[]]></debug>
</interface-response>

Being able to parse this would help logging.

Update public ip getter

Feature request: Multiple hosts

I have a few subdomains all pointing to my homelab. It would be useful if I could provide multiple hosts, and update them all at once.

For example:

docker run --name server.example.com -d --restart unless-stopped -e NC_HOST='server,another,third' -e NC_DOMAIN='example.com' -e NC_PASS='DynamicDDNSPa2w0rd' linuxshots/namecheap-ddns

and the expected result is that server.example.com, another.example.com and third.example.com should now point to my current IP. My workaround for now is to run 5-6 copies, but this calls getPubIP more than necessary.

Logger prints same ip as previous and updated