On May 15, the CentOS project released version 5.5 of its enterprise Linux. It is based on the sources of RHEL5.5 which was released on March, 31.
Unfortunately they – like always – removed the rhn-client-tools and friends from upstream. This is a pity, since it takes more efforts to manage CentOS-installation in Spacewalk.
For the full release notes have a look at http://wiki.centos.org/Manuals/ReleaseNotes/CentOS5.5
Have fun!
spacewalk-1-0-release
Spacewalk 1.0 has been released
Spacewalk is the upstream project for Red Hat’s RHN Satellite software, one of the best systems management software available for Linux Systems.
In the past few weeks one could see a lot of git commits on the source repository of spacewalk. There is no changelog available yet. The road map mentioned compatibility with Apache Tomcat 6.0.x to be able to install spacewalk on Fedora12 and RHEL6.
There should have also been several enhancements in the phyton API and long awaited feature enhancements such as host-renaming (confirmed). Further repository synchronization should be much faster now (Announced in a earlier feature note).
Sorry folks, a lot of “should”, “maybe” etc. I just have been reading the git commit logs and the announcement of the 1.0 release. As long as there is not official changelog available we only can speculate on the precise enhancements.
I’ll install this on my test system soon. If something really uncommon happens or an astonishing new feature appeared, I’ll let you know,
Have fun!
Cobbler Logo
At the moment, shell scripts as triggers wont work with cobbler. This is due to a bug. Unfortunately the developers wont fix it in the next few weeks or even months.
Triggers are a very welcome and powerful method to automate things before, during after installation of a system. At the moment it only works with python scripts. Since not every sysadmin knows python, but everyone knows to write bash scripts, this is a major drawback.
Cobbler is included in RHN Satellite 5.3 but in a quite old version. People tend to use a standalone cobbler install server installed from EPEL. Out of the box Cobbler is only usable on RHN Satellite servers with “deployment” entitlements which are quite expensive. Post-Install triggers can help admins to automate configuration management in RHEL and CentOS environments. For automating configuration with the RHN Satellite you need to have brought the “configuration management” entitlements too. With cobblers triggers you can partially replace the configuration management offered by RHN Satellite. Is this the reason why Red Hat developers are not very keen to solve the issue? I’m talking about ~USD 250 p.a/system.
I’ll keep you posted on the issue….
Red Hat RHN Satellite
In 2003 Red Hat released its RHN Satellite server as a closed source management tool for RHEL and only for RHEL (okay, a legacy support for managing Solaris is available). The satellite is very useful tool for managing systems. Unfortunately it has a quite expensive price tag on it. According to the Red Hats RHN FAQ the bill is USD 13,500/year.
Additionally to the RHN satellite subscription fee you need at least a subscription for the management module which costs another USD 96/year and system. Assume you have a farm of 100 RHEL boxes it costs you about USD 23,100 every year. All prices are list prices.
RHN Satellite comes with an embedded Oracle Database which is from my point of view completely overkill and the driver for the high cost of the subscription. If Red Hat witches to PostgreSQL, I see some chances for lower price tags…
The alternative
In 2008 Red Hat open-sourced the RHN Satellite and named it “Spacewalk” (a pretty cool name 
). Since then the development team already released six versions. The release cycle is quite short in a fast pace.
Release 0.6 is PostgreSQL “ready” whatever that means, I do not know how reliable it is. Full support for PostgreSQL is scheduled with version 1.0 due in Q1/2010. However, for a smaller farm of CentOS systems the free Oracle express edition is good enough.
Installation
The installation is straight forward: Just follow the Instructions how to set up Oracle XE and spacewalk. After the a little tricky installation and configuration of Oracle, you just need to add some yum repositories and run the set up script.
Uploading packages
There are basically to methods to put your RPMs to the Spacewalk server. Either trough yum repository synchronization or via rhnpush. The first method is great if you want to pull a CentOS repository, the second for additional own packages.
Bootstrapping clients
After you installed a new system, you need to add the rhn-client packages to your CentOS system. Unfortunately CentOS removes those packages from the upstream RHEL versions. I hope they will rethink about this.
If you set up your systems by provisioning with Spacewalk, you can automate this task. However I did not got the time yet to test the provisioning stuff with cobbler and kickstart files, its on the to-do list.
Manual bootstrapping works similar to the method like you bootstrap RHEL clients to a RHN Satellite.
Updates and Errata
At the moment this is the tricky part. How to get the upstream errata into Spacewalk? You can use Script that imports digests from the centos-annouce mailing list. Afterwards applying erratas to your systems works fine.
Integrate Spacewalk with other applications
Spacewalk, like RHN Satellite comes with a XML-RPC API which allows you to trigger actions from scrips or (web-)applications. I think about reporting an similar to-be-automated stuff.
Conclusion
If you do not need support from Red Hat, Spacewalk and CentOS can be an alternative for your server farm. If you like more up-to-date systems (e.g. for desktops), Fedora is also supported as a client platform.
Since Red Hat does not provide some kind of Test-Licenses of its products, Spacewalk and CentOS are also a very nice playground for people managing RHEL systems on a daily base either to familiarize them self with the Satellite or doing some tests without bringing the production Satellite into danger.
Further readings
Unfortunately, beside of Red Hats documentations and the Spacewalk Wiki no books and other resources are available. Maybe I should start writing a book? 
Spacewalk Wiki:
https://fedorahosted.org/spacewalk/
Red Hats Spacewalk homepage:
http://www.redhat.com/spacewalk/
Red Hat RHN Satellite documentations:
http://www.redhat.com/docs/manuals/satellite/
Have fun!