= Frequently Asked Questions

== What is the crm shell?

The `crm` shell is a command-line interface to the Pacemaker cluster
resource management stack. If that doesn't make any sense to you, the
easiest way to get up to speed is to go to the
http://clusterlabs.org/[Pacemaker] website and read more about what it
does there.

The `crm` shell provides a simpler interface to configuring Pacemaker
than manipulating the XML of the CIB (Cluster Information Base)
directly. With its command-line style interface, changes to the
cluster can be performed quickly and painlessly. It also works as a
scripting tool, allowing more complicated changes to be applied to the
cluster.

The `crm` shell also functions as a management console, providing a
unified interface to a number of other auxilliary tools related to
Pacemaker and cluster management.

== What distributions does the shell run on?

Many distributions provide packages for the `crm` shell in their
respective package repositories. The best and safest way to obtain the
`crm` shell is via the distribution repositories, so look there first.

The intention is for the `crm` shell to work well on all the major
distributions. Pre-built packages are provided for the
following distros:

    * openSUSE
    * Fedora
    * CentOS
    * Red Hat Linux

More information can be found on the
link:/documentation#_installation[Documentation] page.

== Didn't crm use to be part of Pacemaker?

Yes, initially, the `crm` shell was distributed as part of the
Pacemaker project. It was split into its own, separate project in
2011.

A common misconception is that `crm` has been replaced by `pcs`
(available at https://github.com/feist/pcs[github.com/feist/pcs]). `pcs`
is an alternative command line interface similar to `crm`. Both
projects are being actively developed, with slightly different
goals. Our recommendation is to use whatever shell your distribution
of choice comes with and supports, unless you have a particular
preference or are on a distribution which doesn't bundle either. In
that case, we are obviously biased towards one of the available
choices. ;)

== Command-line is well and good, but is there a web interface?

Yes! Take a look at https://github.com/ClusterLabs/hawk[Hawk].

Hawk uses the `crm` shell as its backend to interact with the cluster.