dynhost-ovh

A simple cronjob to update DynHost on OVH hosting.

forked from yjajkiew/dynhost-ovh

Introduction

This repo provides a script to retrieve the public ip of an host and set a dynhost on OVH accordingly.

A docker image and a Chart is also provided for deployment on kubernetes.

You may also just use cron to run the script.

How it works

1. The command dig is used to retrieve the IP address of your domain name.
2. The command curl (with the website ifconfig.co) is used to retrieve the current public IP address of your machine.
3. The two IPs are compared and if necessary a curl command to OVH is used to update your DynHost with your current public IP address.

Prerequisites

If running on the host

• curl - HTTP calls
• dig - DNS lookup

On ubuntu dig is provided by the dnsutils package

If using the Chart

• Kubernetes 1.21
• helm 3.6.3

Other versions might work but were not tested.

Installing as an hourly CRON

1. Download the dynhost.sh script and put it in the folder /etc/cron.hourly (to check every hour)
2. Add execution permissions to file : chmod +x dynhost.sh
3. Rename dynhost.sh to dynhost (because . at the end of the file name is not allowed in cron)
4. Modify the script with variables : HOST, LOGIN, PASSWORD

Script parameters

The script uses environment variable as parameters.

Name	Description	Value
HOST	Mandatory - The dynhost DNS name to update	""
LOGIN	Mandatory - The dynhost identifier	""
PASSWORD	Mandatory - The dynhost password	""

Installing the Chart

To install the chart:

git clone [REPO_CLONE_URL] && cd dynhost-ovh
helm install [RELEASE] chart \
  --set dynhost.host=[DYNHOST_HOST] \
  --set dynhost.login=[DYNHOST_USERNAME] \
  --set dynhost.password=[DYNHOST_PASSWORD]

Make sure to replace the [...] accordingly.

You may also use a values.yaml file using helm install -f [FILE] ...

Uninstalling the Chart

helm uninstall [RELEASE]

Chart parameters

Common parameters

Name	Description	Value
dynhost.host*	The dynhost DNS name to update	""
dynhost.login*	The dynhost identifier	""
dynhost.password*	The dynhost password	""
dynhost.externalSecretName	The name of a secret containing the script's parameters to use instead of creating one	""
suspend	Wether to suspend the cron or not	no
schedule	The schedule of the cronjob. Use cron syntax	0 * * * * (every hour)
image.repository	The docker image repository	nox404/dynhost-ovh
image.tag	The docker image tag	1.0.0

* dynhost.host, dynhost.login, dynhost.password are Mandatory unless you provide an external secret with dynhost.externalSecretName.

Extended parameters

Name	Description	Value
cronjobApiVersion	Use this if the cronjob api has a different version in your cluster	batch/v1beta1
failedJobsHistoryLimit	The number of failed jobs to keep	1
successfulJobsHistoryLimit	The number of successful jobs to keep	1
backoffLimit	The number of retries to attempt when the job fails	0
image.pullPolicy	Image pull policy	IfNotPresent
imagePullSecrets	Specify image pull secrets	[]
serviceAccount.create	Wether to create a service account	true
serviceAccount.name	Name of the service account to create and/or use	""
podAnnotations	Extra pod annotations	{}
podSecurityContext	The pod security context	{}
securityContext	The container security context	{}
resources	Specify container resources	{}
nodeSelector	Constrain the pod to specific nodes	{}
tolerations	Pod tolerations	[]
affinity	Pod affinities	{}

Building and publishing the Docker image

git clone [REPO_CLONE_URL] && cd dynhost-ovh
docker build -f docker/Dockerfile -t [REPOSITORY]:[TAG] .
docker push [REPOSITORY]:[TAG]