Running Nextcloud as a Podman Container on Rocky Linux

Introduction

This document explains all the required steps needed to build and run a Nextcloud instance as a Podman container on Rocky Linux. What is more, this entire guide was tested on a Raspberry Pi, so it should be compatible with every Rocky-supported processor architecture.

The procedure is broken down into multiple steps, each with its own shell scripts for automation:

1. Installing the podman and buildah packages to manage and build our containers, respectively
2. Creating a base image that will be repurposed for all of the containers we will need
3. Creating a db-tools container image with the required shell scripts for building and running your MariaDB database
4. Creating and running MariaDB as a Podman container
5. Creating and running Nextcloud as a Podman container, using the MariaDB Podman container as backend

You could run most of the commands in the guide manually, but setting up a few bash scripts will make your life much easier, especially when you want to repeat these steps with different settings, variables, or container names.

Note for Beginners:

Podman is a tool for managing containers, specifically OCI (Open Containers Initiative) containers. It is designed to be pretty much Docker-compatible, in that most if not all of the same commands will work for both tools. If "Docker" means nothing to you—or even if you were just curious—you can read more about Podman and how it works on Podman's own website.

buildah is a tool that builds Podman container images based on "DockerFiles".

This guide was designed as an exercise to help people get familiar with running Podman containers in general, and on Rocky Linux specifically.

Prerequisites and assumptions

Here is everything you will need, or need to know, to make this guide work:

• Familiarity with the command line, bash scripts, and editing Linux configuration files.
• SSH access if working on a remote machine.
• A command-line based text editor of your choice. We will be using vi for this guide.
• An internet-connected Rocky Linux machine (again, a Raspberry Pi will work nicely).
• Many of these commands must be run as root, so you will need a root or sudo-capable user on the machine.
• Familiarity with web servers and MariaDB would definitely help.
• Familiarity with containers and maybe Docker would be a definite plus, but is not strictly essential.

Step 01: Install podman and buildah

First, ensure your system is up-to-date:

dnf update

Then you will want to install the epel-release repository for all the extra packages we will be using.

dnf -y install epel-release 

Once that is done, you can update again (which sometimes helps) or just go ahead and install the packages we need:

dnf -y install podman buildah

Once they are installed, run podman --version and buildah --version to ensure everything is working correctly.

To access Red Hat's registry for downloading container images, you will need to run:

vi /etc/containers/registries.conf

Find the section that looks like what you see below. If it is commented out, uncomment it.

[registries.insecure]
registries = ['registry.access.redhat.com', 'registry.redhat.io', 'docker.io'] 
insecure = true

Step 02: Create the base container image

In this guide, we are working as the root user, but you can do this in any home directory. Change to the root directory if you are not already there:

cd /root

Now make all of the directories you will need for your various container builds:

mkdir base db-tools mariadb nextcloud

Now change your working directory to the folder for the base image:

cd /root/base

And make a file called DockerFile. Yes, Podman uses them too.

vi Dockerfile

Copy and paste the following text into your brand new DockerFile.

FROM rockylinux/rockylinux:latest
ENV container docker
RUN yum -y install epel-release ; yum -y update
RUN dnf module enable -y php:7.4
RUN dnf install -y php
RUN yum install -y bzip2 unzip lsof wget traceroute nmap tcpdump bridge-utils ; yum -y update
RUN (cd /lib/systemd/system/sysinit.target.wants/; for i in *; do [ $i == \
systemd-tmpfiles-setup.service ] || rm -f $i; done); \
rm -f /lib/systemd/system/multi-user.target.wants/*;\
rm -f /etc/systemd/system/*.wants/*;\
rm -f /lib/systemd/system/local-fs.target.wants/*; \
rm -f /lib/systemd/system/sockets.target.wants/*udev*; \
rm -f /lib/systemd/system/sockets.target.wants/*initctl*; \
rm -f /lib/systemd/system/basic.target.wants/*;\
rm -f /lib/systemd/system/anaconda.target.wants/*;
VOLUME [ "/sys/fs/cgroup" ]
CMD ["/usr/sbin/init"]

Save and close the previous file, and make a new bash script file:

vi build.sh

Then paste in this content:

#!/bin/bash
clear
buildah rmi `buildah images -q base` ;
buildah bud --no-cache -t base . ;
buildah images -a

Now make your build script executable with:

chmod +x build.sh

And run it:

./build.sh

Wait until it is done, and move on to the next step.

Step 03: Create the db-tools container image

For the purposes of this guide, we are keeping the database setup as simple as we can. You will want to keep track of the following, and modify them as needed:

• Database name: ncdb
• Database user: nc-user
• Database pass: nc-pass
• Your server IP address (we will be using an example IP below)

First, change to the folder where you will be building the db-tools image:

cd /root/db-tools

Now set up some bash scripts that will be used inside the Podman container image. First, make the script that will automatically build your database for you:

vi db-create.sh

Now copy and paste the following code into that file, using your favorite text editor:

#!/bin/bash
mysql -h 10.1.1.160 -u root -p rockylinux << eof
create database ncdb;
grant all on ncdb.* to 'nc-user'@'10.1.1.160' identified by 'nc-pass';
flush privileges;
eof

Save and close, then repeat the steps with the script for deleting databases as needed:

vi db-drop.sh

Copy and paste this code into the new file:

#!/bin/bash
mysql -h 10.1.1.160 -u root -p rockylinux << eof
drop database ncdb;
flush privileges;
eof

Lastly, setup the DockerFile for the db-tools image:

vi Dockerfile

Copy and paste:

FROM localhost/base
RUN yum -y install mysql
WORKDIR /root
COPY db-drop.sh db-drop.sh
COPY db-create.sh db-create.sh

And last but not least, create the bash script to build your image on command:

vi build.sh

The code you will want:

#!/bin/bash
clear
buildah rmi `buildah images -q db-tools` ;
buildah bud --no-cache -t db-tools . ;
buildah images -a

Save and close, then make the file executable:

chmod +x build.sh

And run it:

./build.sh

Step 04: Create the MariaDB container image

You are getting the hang of the process, right? It is time to build that actual database container. Change the working directory to /root/mariadb:

cd /root/mariadb

Make a script to (re)build the container whenever you want:

vi db-init.sh

And here is the code you will need:

Warning

For the purposes of this guide, the following script will delete all Podman Volumes. If you have other applications running with their own volumes, modify/comment the line "podman volume rm --all";

#!/bin/bash
clear
echo " "
echo "Deleting existing volumes if any...."
podman volume rm --all ;
echo " "
echo "Starting mariadb container....."
podman run --name mariadb --label mariadb -d --net host -e MYSQL_ROOT_PASSWORD=rockylinux -v /sys/fs/cgroup:/sys/fs/cgroup:ro -v mariadb-data:/var/lib/mysql/data:Z mariadb ;

echo " "
echo "Initializing mariadb (takes 2 minutes)....."
sleep 120 ;

echo " "
echo "Creating ncdb Database for nextcloud ....."
podman run --rm --net host db-tools /root/db-create.sh ;

echo " "
echo "Listing podman volumes...."
podman volume ls

Here is where you make a script to reset your database whenever you like:

vi db-reset.sh

And here is the code:

#!/bin/bash
clear
echo " "
echo "Deleting ncdb Database for nextcloud ....."
podman run --rm --net host db-tools /root/db-drop.sh ;

echo " "
echo "Creating ncdb Database for nextcloud ....."
podman run --rm --net host db-tools /root/db-create.sh ;

And lastly, here is your build script that will put the whole mariadb container together:

vi build.sh

With its code:

#!/bin/bash
clear
buildah rmi `buildah images -q mariadb` ;
buildah bud --no-cache -t mariadb . ;
buildah images -a

Now just make your DockferFile (vi Dockerfile), and paste in the following single line:

FROM arm64v8/mariadb

Now make your build script executable and run it:

chmod +x *.sh

./build.sh

Step 05: Build and run the Nextcloud container

We are at the final step, and the process pretty much repeats itself. Change to the Nextcloud image directory:

cd /root/nextcloud

Set up your DockerFile first this time, for variety:

vi Dockerfile

Note

This next bit assumes ARM architecture (for the Raspberry Pi), so if you are using another architecture, remember to change this.

And paste in this bit:

FROM arm64v8/nextcloud

Now create your build script:

vi build.sh

And paste in this code:

#!/bin/bash
clear
buildah rmi `buildah images -q nextcloud` ;
buildah bud --no-cache -t nextcloud . ;
buildah images -a

Now, we are going to set up a bunch of local folders on the host server (not in any Podman container), so that we can rebuild our containers and databases without fear of losing all of our files:

mkdir -p /usr/local/nc/nextcloud /usr/local/nc/apps /usr/local/nc/config /usr/local/nc/data

Lastly, we are going to create the script that will actually build the Nextcloud container for us:

vi run.sh

And here is all the code you need for that. Ensure you change the IP address for MYSQL_HOST to the docker container that is running your MariaDB instance.

#!/bin/bash
clear
echo " "
echo "Starting nextloud container....."
podman run --name nextcloud --net host --privileged -d -p 80:80 \
-e MYSQL_HOST=10.1.1.160 \
-e MYSQL_DATABASE=ncdb \
-e MYSQL_USER=nc-user \
-e MYSQL_PASSWORD=nc-pass \
-e NEXTCLOUD_ADMIN_USER=admin \
-e NEXTCLOUD_ADMIN_PASSWORD=rockylinux \
-e NEXTCLOUD_DATA_DIR=/var/www/html/data \
-e NEXTCLOUD_TRUSTED_DOMAINS=10.1.1.160 \
-v /sys/fs/cgroup:/sys/fs/cgroup:ro \
-v /usr/local/nc/nextcloud:/var/www/html \
-v /usr/local/nc/apps:/var/www/html/custom_apps \
-v /usr/local/nc/config:/var/www/html/config \
-v /usr/local/nc/data:/var/www/html/data \
nextcloud ;

Save and close that out, make all of your scripts executable, then run the image building script first:

chmod +x *.sh

./build.sh

To ensure all of your images have been built correctly, run podman images. You should see a list that looks like this:

REPOSITORY                      TAG    IMAGE ID     CREATED      SIZE
localhost/db-tools              latest 8f7ccb04ecab 6 days ago   557 MB
localhost/base                  latest 03ae68ad2271 6 days ago   465 MB
docker.io/arm64v8/mariadb       latest 89a126188478 11 days ago  405 MB
docker.io/arm64v8/nextcloud     latest 579a44c1dc98 3 weeks ago  945 MB

If it all looks right, run the final script to get Nextcloud up and going:

./run.sh

When you run podman ps -a, you should see a list of running containers that looks like this:

CONTAINER ID IMAGE                              COMMAND              CREATED        STATUS            PORTS    NAMES
9518756a259a docker.io/arm64v8/mariadb:latest   mariadbd             3 minutes  ago Up 3 minutes ago           mariadb
32534e5a5890 docker.io/arm64v8/nextcloud:latest apache2-foregroun... 12 seconds ago Up 12 seconds ago          nextcloud

From there, you should be able to point your browser to your server IP address. If you are following along and have the same IP as our example, you can substitute that in here (e.g., http://your-server-ip) and see Nextcloud up and running.

Conclusion

Obviously, this guide would have to be somewhat modified on a production server, especially if the Nextcloud instance is intended to be public-facing. Still, that should give you a basic idea of how Podman works, and how you can set it up with scripts and multiple base images to make rebuilds easier.

Author: Ananda Kammampati

Contributors: Ezequiel Bruni, Steven Spencer, Ganna Zhyrnova