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…
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.
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.
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.
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.
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.
Unfortunately, beside of Red Hats documentations and the Spacewalk Wiki no books and other resources are available. Maybe I should start writing a book?
Red Hats Spacewalk homepage:
Red Hat RHN Satellite documentations: