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.
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 Using Bcfg2 With CentOS for information about building Bcfg2 from source and making your own packages.
Make sure EPEL is a valid repository on your server. The instructions 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 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.
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
Now it is time to get your first machine’s configuration into your Bcfg2 repository. Let’s start with the server itself.
First, replace Pkgmgr with Packages in the plugins line of bcfg2.conf. Then create Packages layout (as per Example usage) in /var/lib/bcfg2
Note
I am using the rawurl syntax here since we are using mrepo to manage our yum mirrors.
<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
<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 Dynamic Group Assignment 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.
Add a base-packages bundle. Let’s see what happens when we just populate it with the yum package.
<Bundle>
<Package name='yum'/>
</Bundle>
You need to reference the bundle from your Metadata. The resulting profile group might look something like this
<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
<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!
Now let’s clear up the unmanaged service entries by adding the following entries to our bundle.
<!-- 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
[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 Writing Bcfg2 Specification for more details.
See installation instructions at Bcfg2 Web Reporting System