PROOF OF CONCEPT

Dockerized Wordpress swarm cluster with self signed certificate.

Services

• Docker Swarm
• GlusterFS
• MariaDB
• Wordpress
• UFW as firewall
• Self signed cert
• HAProxy as Loadbalancer
• Optional: LetsEncrypt integration

Limitations

• There will be a short interruption if the database serving node dies
• Rootless mode is not supported for overlay networks (used in swarm mode)
  • Known rootless limitations

Improve:

• Database multi master cluster
• SELinux configuration on CentOS
• rootless mode via - sysbox?
  • See also swarm with rootless docker & blog.nestybox.com
• setup.sh

Verified OS

• Ubuntu Srv 20.10
• CentOS 7

Verified Docker version

• 20.10.2

HAproxy stats

• Login - https://tld/my-stats
  • User: wpc
  • Pass: wpcstats
• configure user or passwd
  • conf/haproxy.cfg

Usage

• setup 4 dedicated docker nodes
• execute all commands within setup.sh
• start wpcluster
  • cd /home/swarm && wget https://raw.githubusercontent.com/herzog-network/wpcluster_poc/master/startup.sh && chmod 777 startup.sh
  • sudo -H -u swarm bash -c ./startup.sh
• LetsEncrypt (optional)
  • look into create-cert.sh and renew-cert.sh for a short usage description

Links / Credits:

• https://docs.docker.com/engine/install/ubuntu/
• https://docs.docker.com/engine/install/centos/
• https://docs.docker.com/engine/swarm/
• https://docs.gluster.org/en/latest/Install-Guide/Configure/
• https://docs.gluster.org/en/latest/Administrator-Guide/Split-brain-and-ways-to-deal-with-it/#1-replica-3-volume
• https://www.haproxy.com/de/blog/haproxy-on-docker-swarm-load-balancing-and-dns-service-discovery/
• https://omarghader.github.io/haproxy-letsencrypt-docker-certbot-certificates/