path: root/doc/appendix/guides/centos.txt

.. -*- mode: rst -*-

.. _EPEL: http://fedoraproject.org/wiki/EPEL

.. _appendix-guides-centos:

=====================
Quickstart for CentOS
=====================

This is a complete getting started guide for CentOS. With this document
you should be able to install a Bcfg2 server and a Bcfg2 client.

Install Bcfg2
=============

The fastest way to get Bcfg2 onto your system is to use Yum or
your preferred package management tool. We'll be using the ones
that are distributed through EPEL_, but depending on your aversion
to risk you could download an RPM from other places as well. See
:ref:`getting_started-using_bcfg2-with-centos` for information about
building Bcfg2 from source and making your own packages.

Using EPEL
----------

Make sure EPEL_ is a valid repository on your server. The `instructions
<http://fedoraproject.org/wiki/EPEL/FAQ#howtouse>`_ on how to do this
basically say::

    [root@centos ~]# rpm -Uvh http://download.fedora.redhat.com/pub/epel/5/x86_64/epel-release-5-4.noarch.rpm

.. note::

    You will have to adjust this command to match your architecture and
    the current EPEL release.

Install the bcfg2-server and bcfg2 RPMs::

    [root@centos ~]# yum install bcfg2-server bcfg2

Your system should now have the necessary software to use Bcfg2. The
next step is to set up your Bcfg2 :term:`repository`.

Initialize your repository
==========================

Now that you're done with the install, you need to initialize your
repository and setup your ``/etc/bcfg2.conf``. ``bcfg2-admin init``
is a tool which allows you to automate this::

    [root@centos ~]# bcfg2-admin init
    Store bcfg2 configuration in [/etc/bcfg2.conf]:
    Location of bcfg2 repository [/var/lib/bcfg2]:
    Input password used for communication verification (without echoing; leave blank for a random):
    What is the server's hostname: [centos]
    Input the server location [https://centos:6789]:
    Input base Operating System for clients:
    1: Redhat/Fedora/RHEL/RHAS/Centos
    2: SUSE/SLES
    3: Mandrake
    4: Debian
    5: Ubuntu
    6: Gentoo
    7: FreeBSD
    : 1
    Generating a 2048 bit RSA private key
    .........................+++
    ..................+++
    writing new private key to '/etc/bcfg2.key'
    -----
    Signature ok
    subject=/C=US=ST=Illinois/L=Argonne/CN=centos
    Getting Private key
    Repository created successfuly in /var/lib/bcfg2

Change responses as necessary.

Start the server
================

You are now ready to start your bcfg2 server for the first time::

    [root@centos ~]# /sbin/service bcfg2-server start

To verify that everything started ok, look for the running daemon and check the logs::

    [root@centos ~]# /etc/init.d/service bcfg2-server status
    [root@centos ~]# tail /var/log/messages
    Mar 29 12:42:26 centos bcfg2-server[5093]: service available at https://centos:6789
    Mar 29 12:42:26 centos bcfg2-server[5093]: serving bcfg2-server at https://centos:6789
    Mar 29 12:42:26 centos bcfg2-server[5093]: serve_forever() [start]
    Mar 29 12:42:41 centos bcfg2-server[5093]: Handled 16 events in 0.007s

Run bcfg2 to be sure you are able to communicate with the server::

    [root@centos ~]# bcfg2 -vqn
    No ca is specified. Cannot authenticate the server with SSL.
    No ca is specified. Cannot authenticate the server with SSL.
    Loaded plugins: fastestmirror
    Loading mirror speeds from cached hostfile
    Excluding Packages in global exclude list
    Finished
    Loaded tool drivers:
     Action Chkconfig POSIX YUM

    Phase: initial
    Correct entries: 0
    Incorrect entries: 0
    Total managed entries: 0
    Unmanaged entries: 208


    Phase: final
    Correct entries: 0
    Incorrect entries: 0
    Total managed entries: 0
    Unmanaged entries: 208

    No ca is specified. Cannot authenticate the server with SSL.

The ca message is just a warning, meaning that the client does not
have sufficient information to verify that it is talking to the
correct server. This can be fixed by distributing the ca certificate
from the server to all clients. By default, this file is available in
``/etc/bcfg2.crt`` on the server. Copy this file to the client (with a
bundle) and add the ca option to ``bcfg2.conf`` pointing at the file,
and the client will be able to verify it is talking to the correct server
upon connection::

    [root@centos ~]# cat /etc/bcfg2.conf


    [communication]
    password = N41lMNeW
    ca = /etc/bcfg2.crt

    [components]
    bcfg2 = https://centos:6789

Now if you run the client, no more warning::

    [root@centos ~]# bcfg2 -vqn
    Loaded plugins: fastestmirror
    Loading mirror speeds from cached hostfile
    Excluding Packages in global exclude list
    Finished
    Loaded tool drivers:
     Action Chkconfig POSIX YUM

    Phase: initial
    Correct entries: 0
    Incorrect entries: 0
    Total managed entries: 0
    Unmanaged entries: 208


    Phase: final
    Correct entries: 0
    Incorrect entries: 0
    Total managed entries: 0
    Unmanaged entries: 208

Bring your first machine under Bcfg2 control
============================================

Now it is time to get your first machine's configuration into your
Bcfg2 :term:`repository`. Let's start with the server itself.


Setup the :ref:`server-plugins-generators-packages` plugin
----------------------------------------------------------

First, replace **Pkgmgr** with **Packages** in the plugins
line of ``bcfg2.conf``. Then create Packages layout (as per
:ref:`packages-exampleusage`) in ``/var/lib/bcfg2``

.. note:: I am using the rawurl syntax here since we are using `mrepo`_
          to manage our yum mirrors.

.. _mrepo: http://dag.wieers.com/home-made/mrepo/

.. code-block:: xml

    <Sources>
        <Group name="centos5">
            <!-- CentOS 5 sources -->
            <Source type="yum"
                    rawurl="http://mrepo/centos5-x86_64/RPMS.os">
                <Arch>x86_64</Arch>
            </Source>
            <Source type="yum"
                    rawurl="http://mrepo/centos5-x86_64/RPMS.updates">
                <Arch>x86_64</Arch>
            </Source>
            <Source type="yum"
                    rawurl="http://mrepo/centos5-x86_64/RPMS.extras">
                <Arch>x86_64</Arch>
            </Source>
        </Group>
    </Sources>

To make these sources apply to our centos 5 clients, we need to modify
our Metadata. Let's add a **centos5** group which inherits a
**centos** group (this should replace the existing **redhat** group)
present in ``/var/lib/bcfg2/Metadata/groups.xml``. The resulting file
should look something like this

.. code-block:: xml

    <Groups version='3.0'>
       <Group profile='true' public='true' default='true' name='basic'>
          <Group name='centos-5'/>
       </Group>
       <Group name='centos-5'>
          <Group name='centos'/>
       </Group>
       <Group name='ubuntu'/>
       <Group name='debian'/>
       <Group name='freebsd'/>
       <Group name='gentoo'/>
       <Group name='centos'/>
       <Group name='suse'/>
       <Group name='mandrake'/>
       <Group name='solaris'/>
    </Groups>

.. note::
    When editing your xml files by hand, it is useful to occasionally run
    `bcfg2-lint` to ensure that your xml validates properly.

The final thing we need is for the client to have the proper arch
group membership. For this, we will make use of the
:ref:`server-plugins-probes-dynamic-groups` capabilities of the Probes
plugin. Add Probes to your plugins line in ``bcfg2.conf`` and create
the Probe.::

    [root@centos ~]# grep plugins /etc/bcfg2.conf
    plugins = Bundler,Cfg,...,Probes
    [root@centos ~]# mkdir /var/lib/bcfg2/Probes
    [root@centos ~]# cat /var/lib/bcfg2/Probes/groups
    #!/bin/sh

    echo "group:`uname -m`"

Now we restart the bcfg2-server::

    [root@centos ~]# /etc/init.d/bcfg2-server restart

If you now ``tail -f /var/log/messages``, you will see the Packages
plugin in action, updating the cache.

Start managing packages
-----------------------

Add a base-packages bundle. Let's see what happens when we just populate
it with the *yum* package.

.. code-block:: xml

    <Bundle>
      <Package name='yum'/>
    </Bundle>

You need to reference the bundle from your Metadata. The resulting
profile group might look something like this

.. code-block:: xml

    <Group profile='true' public='true' default='true' name='basic'>
       <Bundle name='base-packages'/>
       <Group name='centos5'/>
    </Group>

Now if we run the client, we can see what this has done for us.::

    [root@centos ~]# bcfg2 -vqn
    Running probe groups
    Probe groups has result:
    x86_64
    Loaded plugins: fastestmirror
    Loading mirror speeds from cached hostfile
    Excluding Packages in global exclude list
    Finished
    Loaded tool drivers:
     Action Chkconfig POSIX YUM
            Package pam failed verification.

    Phase: initial
    Correct entries: 94
    Incorrect entries: 1
    Total managed entries: 95
    Unmanaged entries: 113

    In dryrun mode: suppressing entry installation for:
      Package:pam

    Phase: final
    Correct entries: 94
    Incorrect entries: 1
     Package:pam
    Total managed entries: 95
    Unmanaged entries: 113

Interesting, our **pam** package failed verification. What does this
mean? Let's have a look::

    [root@centos ~]# rpm --verify pam
    ....L... c /etc/pam.d/system-auth

Sigh, it looks like the default RPM install for pam fails to verify
using its own verification process (trust me, it's not the only one). At
any rate, I was able to get rid of this particular issue by removing the
symlink and running ``yum reinstall pam``.

As you can see, the Packages plugin has generated the dependencies
required for the yum package automatically. The ultimate goal should
be to move all the packages from the **Unmanaged** entries section to
the **Managed** entries section. So, what exactly *are* those Unmanaged
entries?::

    [root@centos ~]# bcfg2 -veqn
    Running probe groups
    Probe groups has result:
    x86_64
    Loaded plugins: fastestmirror
    Loading mirror speeds from cached hostfile
    Excluding Packages in global exclude list
    Finished
    Loaded tool drivers:
     Action Chkconfig POSIX YUM
    Extra Package openssh-clients 4.3p2-36.el5_4.4.x86_64.
    Extra Package libuser 0.54.7-2.1el5_4.1.x86_64.
    ...

    Phase: initial
    Correct entries: 95
    Incorrect entries: 0
    Total managed entries: 95
    Unmanaged entries: 113


    Phase: final
    Correct entries: 95
    Incorrect entries: 0
    Total managed entries: 95
    Unmanaged entries: 113
     Package:at
     Package:avahi
     Package:avahi-compat-libdns_sd
     ...

Now you can go through these and continue adding the packages you want
to your Bundle. After a while, I ended up with a minimal bundle that
looks like this

.. code-block:: xml

    <Bundle>
      <Package name='bcfg2-server'/>
      <Package name='exim'/>
      <Package name='grub'/>
      <Package name='kernel'/>
      <Package name='krb5-workstation'/>
      <Package name='m2crypto'/>
      <Package name='openssh-clients'/>
      <Package name='openssh-server'/>
      <Package name='prelink'/>
      <Package name='redhat-lsb'/>
      <Package name='rpm-build'/>
      <Package name='rsync'/>
      <Package name='sysklogd'/>
      <Package name='vim-enhanced'/>
      <Package name='yum'/>
    </Bundle>

Now when I run the client, you can see I have only one unmanaged
package::

    [root@centos ~]# bcfg2 -veqn
    Running probe groups
    Probe groups has result:
    x86_64
    Loaded plugins: fastestmirror
    Loading mirror speeds from cached hostfile
    Excluding Packages in global exclude list
    Finished
    Loaded tool drivers:
     Action Chkconfig POSIX YUM

    Phase: initial
    Correct entries: 187
    Incorrect entries: 0
    Total managed entries: 187
    Unmanaged entries: 16


    Phase: final
    Correct entries: 187
    Incorrect entries: 0
    Total managed entries: 187
    Unmanaged entries: 16
     Service:atd
     Service:avahi-daemon
     Service:bcfg2-server
     ...

Now, running the client shows only unmanaged Service entries. Woohoo!

Manage services
---------------

Now let's clear up the unmanaged service entries by adding the following
entries to our bundle.

.. code-block:: xml

    <!-- basic services -->
    <Service name='atd'/>
    <Service name='avahi-daemon'/>
    <Service name='bcfg2-server'/>
    <Service name='crond'/>
    <Service name='cups'/>
    <Service name='gpm'/>
    <Service name='lvm2-monitor'/>
    <Service name='mcstrans'/>
    <Service name='messagebus'/>
    <Service name='netfs'/>
    <Service name='network'/>
    <Service name='postfix'/>
    <Service name='rawdevices'/>
    <Service name='sshd'/>
    <Service name='syslog'/>

...and bind them in Rules

.. code-block:: xml

    [root@centos ~]# cat /var/lib/bcfg2/Rules/services.xml
    <Rules priority='1'>
      <!-- basic services -->
      <Service type='chkconfig' status='on' name='atd'/>
      <Service type='chkconfig' status='on' name='avahi-daemon'/>
      <Service type='chkconfig' status='on' name='bcfg2-server'/>
      <Service type='chkconfig' status='on' name='crond'/>
      <Service type='chkconfig' status='on' name='cups'/>
      <Service type='chkconfig' status='on' name='gpm'/>
      <Service type='chkconfig' status='on' name='lvm2-monitor'/>
      <Service type='chkconfig' status='on' name='mcstrans'/>
      <Service type='chkconfig' status='on' name='messagebus'/>
      <Service type='chkconfig' status='on' name='netfs'/>
      <Service type='chkconfig' status='on' name='network'/>
      <Service type='chkconfig' status='on' name='postfix'/>
      <Service type='chkconfig' status='on' name='rawdevices'/>
      <Service type='chkconfig' status='on' name='sshd'/>
      <Service type='chkconfig' status='on' name='syslog'/>
    </Rules>

Now we run the client and see there are no more unmanaged entries!::

    [root@centos ~]# bcfg2 -veqn
    Running probe groups
    Probe groups has result:
    x86_64
    Loaded plugins: fastestmirror
    Loading mirror speeds from cached hostfile
    Excluding Packages in global exclude list
    Finished
    Loaded tool drivers:
     Action Chkconfig POSIX YUM

    Phase: initial
    Correct entries: 205
    Incorrect entries: 0
    Total managed entries: 205
    Unmanaged entries: 0


    Phase: final
    Correct entries: 205
    Incorrect entries: 0
    Total managed entries: 205
    Unmanaged entries: 0

.. warning::

    This basic bundle is created mainly for the purposes of getting you
    to a completely managed client. It is recommended that you create
    bundles for appropriate services due to the way bundle updates are
    managed. Please see :ref:`unsorted-writing_specification` for more
    details.

Dynamic (web) reports
=====================

See installation instructions at :ref:`reports-dynamic`

Next Steps
==========

:ref:`getting_started-index-next-steps`