There are some differences on setting up RRDReST on CentOS 8, Almalinux 9 vs CentOS 7

If you are setting this up to use with LibreNMS and Grafana, check out the rest of the this article. https://www.incredigeek.com/home/setting-up-grafana-on-librenms/

Installing RRDReST

All the docker commands have been swapped out for podman.

1. Install Docker
2. Create a compose file
3. Run compose file to create container

Install docker

Podman is default on CentOS 8 and later and is, for the most part, a drop in replacement for Docker.

sudo yum install -y podman podman-compose
sudo systemctl enable podman

Create a Podman / Docker network to use. We’ll use this to assign a static IP address to the container. We’ll call the network rrdnet, and we’ll use the 10.89.2.0/24 range.

sudo podman network create --subnet=10.89.2.0/24 rrdnet

Create podman-compose file

Create a docker compose file

vi podman-compose.yml

Add the following

version: "3.5"
services:
  rrdrest:
    image: michaelwadman/rrdrest:latest
    container_name: rrdrest
    restart: always
    volumes:
      - "/opt/librenms/rrd:/opt/librenms/rrd:Z"
    environment:
      - TZ=America/Denver
    networks:
      rrdnet:
        ipv4_address: 10.89.2.2
        ipam:
          driver: default
          config:
            - subnet: 10.89.2.0/24
networks:
  rrdnet:
    external: true

Change the TZ to your time zone. If you have issues with the graphs, most likely something is off with the time zone between this container and Grafana/LibreNMS server

Note that the :Z is needed for SELinux to allow RRDReST to access the sub folders. AKA. the rrd files.

The container should have a 10.89.2.2 IP address. You can take all the networking sections out, and the container will receive DHCP. The problem is that the IP can change, breaking our graphs in Grafana.

Run RRDReST Container

Save the file. Then start and setup the container with

sudo podman-compose up -d

You will need your docker container IP address to setup the connection in Grafana. If you used the above docker-compose config, then it should be 10.89.2.2.

sudo docker exec -it rrdrest ip addr | grep eth0

Configure RRDRest to start on system boot with systemd

The “restart: always” option does not appear to work on systems with podman. We can create a systemd service instead.

Use the following command to automatically create a systemd file.

sudo podman generate systemd rrdrest

Copy the contents to a new file in /etc/systemd/system/

/etc/systemd/system/rrdrest.service

If you end up deleting the rrdrest container, you’ll need to update the systemd file again. You may need also need to run “systemctl daemon-reload”

Enable the new service with

systemctl enable rrdrest

Congratulations. RRDReST is now setup and running.

You can verify it’s running by checking with Podman / Docker.

sudo podman ps

You can also ping it

ping 10.89.2.2