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.
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 repo.percona.com
as the charm installs packages direct from the Percona respositories. If you
are using squid-deb-proxy, follow the steps below:
echo "repo.percona.com" | 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
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=10.0.3.200
juju deploy hacluster
juju add-relation hacluster percona-cluster
Clients can then access using the vip provided. This vip will be passed to
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.