Pcs is a Corosync and Pacemaker configuration tool. It permits users to easily view, modify and create Pacemaker based clusters. Pcs contains pcsd, a pcs daemon, which operates as a remote server for pcs and provides a web UI.

These are the runtime dependencies of pcs and pcsd:

• python 2.7+
• python-lxml / python3-lxml
• python-pycurl / python3-pycurl
• python-setuptools / python3-setuptools
• ruby 2.0.0+
• killall (package psmisc)
• openssl
• corosync
• pacemaker

It is also recommended to have these:

• python-clufter / python3-clufter
• liberation fonts (package liberation-sans-fonts or fonts-liberation or fonts-liberation2)
• overpass fonts (package overpass-fonts)

If you plan to manage Corosync 1.x based clusters, you will also need:

• cman
• ccs

It is however highly recommended for new clusters to use Corosync 2.x. Support for Corosync 1.x and CMAN has been deprecated in 0.9.160 and will be removed.

Apart from the dependencies listed above, these are also required for installation:

• python development files (package python-devel / python3-devel)
• ruby development files (package ruby-devel)
• rubygems
• rubygem bundler (package rubygem-bundler or ruby-bundler or bundler)
• gcc
• gcc-c++
• PAM development files (package pam-devel or libpam0g-dev)
• FFI development files (package libffi-devel or libffi-dev)
• fontconfig
• printf (package coreutils)
• redhat-rpm-config if you are using Fedora
• wget (to download bundled libraries)

During the installation, all required rubygems are automatically downloaded and compiled.

To install pcs and pcsd run the following in terminal:

# tar -xzvf pcs-0.9.160.tar.gz
# cd pcs-0.9.160
# make install
# make install_pcsd

If you are using GNU/Linux with systemd, it is now time to:

# systemctl daemon-reload

Start pcsd and make it start on boot:

# systemctl start pcsd
# systemctl enable pcsd

Currently this is built into Fedora, RHEL and its clones and Debian and its derivates.

• Fedora package git repositories
• Current Fedora .spec
• Debian-HA project home page

• Authenticate cluster nodes

  Set the same password for the hacluster user on all nodes.

  # passwd hacluster

  To authenticate the nodes, run the following command on one of the nodes (replacing node1, node2, node3 with a list of nodes in your future cluster). Specify all your cluster nodes in the command. Make sure pcsd is running on all nodes.

  # pcs cluster auth node1 node2 node3 -u hacluster

• Create a cluster

  To create a cluster run the following command on one node (replacing cluster_name with a name of your cluster and node1, node2, node3 with a list of nodes in the cluster). --start and --enable will start your cluster and configure the nodes to start the cluster on boot respectively.

  # pcs cluster setup --name cluster_name node1 node2 node3 --start --enable

• Check the cluster status

  After a few moments the cluster should startup and you can get the status of the cluster.

  # pcs status

• Add cluster resources

  After this you can add stonith agents and resources:

  # pcs -h stonith create

  and

  # pcs -h resource create

Apart from command line interface you can use web user interface to view and configure your cluster. To access the web UI open a browser to the following URL (replace nodename with an address of your node):

https://nodename:2224

Login as the hacluster user.

ClusterLabs website is an excellent place to learn more about Pacemaker clusters.

• ClusterLabs quick start
• Clusters from Scratch
• ClusterLabs documentation page

If you have any bug reports or feature requests please feel free to open a github issue on the pcs project.

Alternatively you can use ClusterLabs users mailinglist which is also a great place to ask Pacemaker clusters related questions.