percona cluster


Percona XtraDB Cluster provides an active/active MySQL
compatible alternative implemented using the Galera
synchronous replication extensions.


Percona XtraDB Cluster is a high availability and high scalability solution for
MySQL clustering. Percona XtraDB Cluster integrates Percona Server with the
Galera library of MySQL high availability solutions in a single product package
which enables you to create a cost-effective MySQL cluster.

This charm deploys Percona XtraDB Cluster onto Ubuntu.


WARNING: Its critical that you follow the bootstrap process detailed in this
document in order to end up with a running Active/Active Percona Cluster.

Proxy Configuration

If you are deploying this charm on MAAS or in an environment without direct
access to the internet, you will need to allow access to
as the charm installs packages direct from the Percona respositories. If you
are using squid-deb-proxy, follow the steps below:

echo "" | sudo tee /etc/squid-deb-proxy/mirror-dstdomain.acl.d/40-percona
sudo service squid-deb-proxy restart


The first service unit deployed acts as the seed node for the rest of the
cluster; in order for the cluster to function correctly, the same MySQL passwords
must be used across all nodes:

cat > percona.yaml << EOF
    root-password: my-root-password
    sst-password: my-sst-password

Once you have created this file, you can deploy the first seed unit:

juju deploy --config percona.yaml percona-cluster

Once this node is full operational, you can add extra units one at a time to the

juju add-unit percona-cluster

A minimium cluster size of three units is recommended.

In order to access the cluster, use the hacluster charm to provide a single IP

juju set percona-cluster vip=
juju deploy hacluster
juju add-relation hacluster percona-cluster

Clients can then access using the vip provided. This vip will be passed to
related services:

juju add-relation keystone percona-cluster


Note that Percona XtraDB Cluster is not a 'scale-out' MySQL solution; reads
and writes are channelled through a single service unit and synchronously
replicated to other nodes in the cluster; reads/writes are as slow as the
slowest node you have in your deployment.


(string) Network interface on which to place the Virtual IP
(int) Netmask that will be used for the Virtual IP
(string) Re-sync account password for new cluster nodes; must be configured pre-deployment for Active-Active clusters.
(string) Package install location for Percona XtraDB Cluster (defaults to distro for >= 14.04)
(string) Virtual IP to use to front Percona XtraDB Cluster in active/active HA configuration
(int) Default multicast port number that will be used to communicate between HA Cluster nodes.
(int) Maximum connections to allow. -1 means use the server's compiled in default.
(string) Default network interface on which HA cluster will bind to communication with the other members of the HA Cluster.
(string) How much data do you want to keep in memory in the DB. This will be used to tune settings in the database server appropriately. Suffix this value with 'K','M','G', or 'T' to get the relevant kilo/mega/etc. bytes. If suffixed with %, one will get that percentage of RAM devoted to dataset.
(string) Root password for MySQL access; must be configured pre-deployment for Active-Active clusters.