Debugging Docker Apps Features

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Debugging Docker Apps Features

We’ve recently released a Docker Apps feature (from v2.3.5 and above) which allows you to deploy apps within Docker. To use this feature, we’ve created three easy video tutorials for you.

  1. How to Assign Package in Docker App
  2. How to deploy WordPress within Docker
  3. How to Deploy Self-Host N8N

Right now we support WordPress and N8N apps within Docker and more to come later.

How to find issues with Docker Apps

With any feature in CyberPanel you can use our debugging guide to find out the root cause of any problem. So I highly recommend you read our CyberPanel Debugging Guide.

OK, so before you start debugging, run following on terminal

 touch /usr/local/CyberCP/debug

Now you will start getting debug logs by running the command

tail -f /home/cyberpanel/error-logs.txt

Once you run the above command now go back and create Docker App again.

Error 1: Docker or Docker Compose Not Found

Normally CyberPanel will install Docker and Docker Compose for you before creating an app. But if for some reason it goes not get installed, you can install it using following command.

For Ubuntu Based Servers

apt-get install -y docker.io docker-compose
systemctl start docker
systemctl enable docker

If for some reason you can not install using above commands, you can also follow official Docker guide for installing Docker and Docker Compose and it will also work with CyberPanel.

Please note that you need both Docker and Docker Compose.

Tip: Remove and do fresh Docker installation via cli if installation is failing.

For Centos/AlmaLinux/CloudLinux

dnf config-manager --add-repo=https://download.docker.com/linux/centos/docker-ce.repo
sudo dnf install docker-ce docker-ce-cli containerd.io docker-compose-plugin --nobest
systemctl start docker
systemctl enable docker

If for some reason you can not install using above commands, you can also follow official Docker guide for installing Docker and Docker Compose and it will also work with CyberPanel.

Please note that you need both Docker and Docker Compose.

Tip: Remove and do fresh Docker installation via cli if installation is failing.

Error 2: ERROR: Failed to Setup IP tables: Unable to enable SKIP DNAT rule: (iptables failed: iptables –wait -t nat -I DOCKER -i br-d105aa4cf6c4 -j RETURN: iptables: No chain/target/match by that name. (exit status 1))

It seems like there’s an issue with setting up IP tables, specifically related to enabling the SKIP DNAT rule. The error message indicates that the chain/target/match required for this rule is missing, which is causing the iptables command to fail.

To troubleshoot and resolve this issue, you can try the following steps:

  1. Check if the required modules for iptables are loaded. Sometimes, certain modules might not be loaded properly, causing issues with iptables rules. You can check the loaded modules using the following command:
   lsmod | grep iptable
  1. Make sure that the necessary iptables modules are installed. You can reinstall iptables to ensure all required components are present:
   sudo apt-get install --reinstall iptables
  1. Verify if the chain “DOCKER” exists in the “nat” table. You can do this by listing the chains in the “nat” table:
   sudo iptables -t nat -L
  1. If the “DOCKER” chain doesn’t exist, you may need to recreate it. You can recreate it using the following command:
   sudo iptables -t nat -N DOCKER
  1. After recreating the “DOCKER” chain, retry enabling the SKIP DNAT rule:
   sudo iptables -t nat -I DOCKER -i br-d105aa4cf6c4 -j RETURN
  1. Finally, restart the Docker service to apply the changes:
   sudo service docker restart

These steps should help you diagnose and resolve the issue with setting up IP tables and enabling the SKIP DNAT rule. If the issue persists, there may be other underlying issues with your system configuration that need to be addressed.

Error 3: Using Docker with csf

Learn more about this problem: Docker and CSF Problems

If still the issue is not resolved, try solution in Error 1 by completely removing and re-installing Docker

Retry App Creation

If you are able to resolve all issues then re-try app creation still keeping eyes on logs to see what is wrong.

Faqs

Q. Just want to confirm if docker apps use persistent storage so that data is not lost when the server is restarted.

Answer: Yes data is persistent, if container restarts your data stays there.

Q. Is there a guide for updating existing docker apps?

We will make one and update the link here.

Q. How can one add new docker apps that are currently not available on the one-click install?

You can not because it is a customized and optmized set up, we will add more apps to our Docker Apps.

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