Applications

Tips and Tricks about some of my Docker Applications.

Apache Guacamole

Apache Guacamole is a clientless remote desktop gateway. It supports standard protocols like VNC, RDP, and SSH.

Apache Guacamole

Docker Installation on ARM64

Apache Guacamole is a powerful tool for managing remote connections, and installing it on a Raspberry Pi 4 with Docker allows for easy, remote access from almost anywhere

Prerequisites

  1. Raspberry Pi 4
  2. Docker installed

Docker Compose Setup

For this installation, we will use a compose.yaml file with Docker Compose to manage the Guacamole installation.

I’m using the flcontainers/guacamole Docker image, which is compatible with the ARM64 architecture, unlike the official image.

Here’s what the compose.yaml file should look like:

services:
    guacamole_app:
        container_name: guacamole_app
        image: flcontainers/guacamole:latest
        restart: unless-stopped
        ports:
            - 8094:8080
        volumes:
            - guacamole_app-config:/config
            - /etc/localtime:/etc/localtime:ro
        environment:
            TZ: 'Europe/Brussels'
        healthcheck:
            test: curl -f -k http://127.0.0.1:8080/ || exit 1
            interval: 15s
            timeout: 10s
            retries: 5

volumes:
    guacamole_app-config:
        name: guacamole_app-config

Installation

Once you’ve created the compose.yaml file, navigate to the directory where it’s stored and run the following command:

docker compose up -d

This command will pull the Guacamole image and install it on your Raspberry Pi.

Using Apache Guacamole

After the installation, you can access the Guacamole web interface by visiting http://<YOUR_RPI_IP>:8094

Username: guacadmin
Password: guacadmin

With this setup, you now have Apache Guacamole running on your Raspberry Pi 4, allowing easy remote desktop access and management.

Happy me! 🌱

Bookstack

BookStack is a simple, open-source, self-hosted, easy-to-use platform for organising and storing information.

Bookstack

Changing the Base URL

Sometimes, you need to change the base URL of Bookstack, for example, when you switch from the localhost address to the internet exposed address.

Docker Compose

In your compose.yaml, modify the following environment variable:

APP_URL=<new_url>

Bookstack Container

Open a terminal and type:

docker exec -it <bookstack_container> php /app/www/artisan bookstack:update-url <old_url> <new_url>

Clear Cache

Open a terminal and type:

docker exec -it <bookstack_container>  php /app/www/artisan cache:clear

Paperless-ngx

Paperless-ngx is a document management system that transforms your physical documents into a searchable online archive.

Paperless-ngx

Backup & Restore

Here is the procedure to backup and restore the Paperless-NGX application and all of its data.

Backup

On a terminal, enter the following command:

docker compose exec -T <paperless_webserver> document_exporter -z ../export

Where:

Restore

You'll need to unzip the previous export!

On a terminal, enter the following command:

docker compose exec -T <paperless_webserver> document_importer ../export/<unzipped_directory>/

Where:

Paperless-ngx

Consumption fails with "Ghostscript PDF/A rendering failed"

When updating Paperless-NGX, you may get the following error:

Consumption fails with "Ghostscript PDF/A rendering failed" Newer versions of OCRmyPDF will fail if it encounters errors during processing. This is intentional as the output archive file may differ in unexpected or undesired ways from the original. As the logs indicate, if you encounter this error you can set PAPERLESS_OCR_USER_ARGS: '{"continue_on_soft_render_error": true}' to try to 'force' processing documents with this issue.

To fix this, you can:

  1. Go to your paperless web interface
  2. Go to Configuration menu
  3. Go to OCR Settings tab
  4. In the OCR Arguments tile, enter {"continue_on_soft_render_error": true}
  5. Save

And, the error is fixed!

Paperless-ngx

Creating a Super User

If you don't have a super user with your Paperless-NGX installation, you can create one with a command.

docker compose exec -it <PAPERLESS CONTAINER> createsuperuser

> Username (leave blank to use 'paperless'): 
> Email address: 
> Password: 
> Password (again):
> Superuser created successfully.

ntfy

ntfy lets you send push notifications to your phone or desktop via scripts from any computer, using simple HTTP PUT or POST requests.

ntfy

🔔 Low Space

Script

#!/bin/bash

mingigs=20
avail=$(df | awk '$6 == "/" && $4 < '$mingigs' * 1024*1024 { print $4/1024/1024 }')

if [ -n "$avail" ]; then
  curl \
      -H "Title: Low Disk Space" \
      -H "Priority: urgent" \
      -H "Tags: warning,cd" \
      -d "Hello TTBB! Only $avail GB available on the root disk. Better clean that up." \
      https://notify.boreux.work/raspberrypi?auth=<TOKEN>
fi

Cron

0  *    * * *   root    /bin/bash /root/ntfy/low-disk-space.sh
ntfy

⛔️ SSH Access

Script

#!/bin/bash
if [ "${PAM_TYPE}" = "open_session" ]; then
  curl \
      -H "Title: SSH Login" \
      -H "Priority: urgent" \
      -H "Tags: warning,door" \
      -d "Hello TTBB! There was an SSH login with user ${PAM_USER} from ${PAM_RHOST} host" \
      https://notify.boreux.work/pihole?auth=<TOKEN>
fi

/etc/pam.d/sshd

At the end of the file, add the following line:

session optional pam_exec.so /root/ntfy/ssh-login.sh
ntfy

🐚 Useful Commands

Creating an Administrator

docker exec -it <NTFY_CONTAINER_NAME> ntfy user add --role=admin <USERNAME>

Vikunja

The to-do app to organize your life

Vikunja

Quick Add Magic

Quick Add Magix Syntax Cheatsheet

Labels - *

*"Label with spaces"

Project - +

+"Project with spaces"

Due Date and Time

The date format is: MM/DD/YYYY

02/17/2021 at 17:00

Assignee

@ttbb

Examples