How to bootstrap a Patroni cluster using vagrant

This Vagrantfile is bootstrapping a fresh cluster based on CentOS7 with:

• servers e1, e2 and e3 hosting a etcd cluster
• servers p1 and p2 hosting a Patroni/PostgreSQL cluster
• watchdog enabled

Note that NTP is enabled by default (using chrony) in the vagrant box used (centos/7). No need to set it up ourselves.

Prerequisites:

You need vagrant and vagrant-libvirt. Everything is tested with versions 2.0.2 and 0.0.40. Please, report your versions if it works with inferior ones.

apt install make vagrant vagrant-libvirt libvirt-clients # for Debian-like
yum install make vagrant vagrant-libvirt libvirt-client # for RH-like
dnf install make vagrant vagrant-libvirt libvirt-client # for recent RH-like
systemctl enable --now libvirtd

Creating the cluster

To create the cluster, run:

cd vagrant-patroni
make all

After some minutes and tons of log messages, you can connect to your servers using eg.:

vagrant ssh p1

Setup patronictl:

/usr/local/bin/patronictl configure \
  --config-file "${HOME:?}/.config/patroni/patronictl.yaml" \
  --dcs "etcd://10.20.30.55:2379" \
  --namespace "/service"

Play with the cluster!

/usr/local/bin/patronictl list patroni-demo
/usr/local/bin/patronictl switchover --help
/usr/local/bin/patronictl switchover patroni-demo --master p2 --candidate p1 --force

Destroying the cluster

To destroy your cluster, run:

vagrant destroy -f

Tips

Find all existing VM created by vagrant on your system:

vagrant global-status