The standard XenServer 5.6 does not have a template for the latest CentOS 5.5 distribution. But this is not a big problem: simply install CentOS 5.3 first, then upgrade to the latest CentOS 5.5 release.

1. Install CentOS 5.3 using the CentOS-5.3-i386-bin-DVD.iso image
2. Run yum update. This will start the (lengthy) update process to CentOS 5.5. After installation, the version can be verified using rpm -qa | grep centos-release.
3. Install the XenServer tools.
4. At this point CentOS 5.5 is properly installed. The following notes are some additional configuration changes and serve as a documentation to one of my personal systems.
5. Install the RPMForge Repo (see also http://wiki.centos.org/AdditionalResources/Repositories/RPMForge:)

   #wget http://packages.sw.be/rpmforge-release/rpmforge-release-0.5.1-1.el5.rf.i386.rpm wget http://packages.sw.be/rpmforge-release/rpmforge-release-0.5.1-1.el5.rf.x86_64.rpm rpm --import http://apt.sw.be/RPM-GPG-KEY.dag.txt rpm -K rpmforge-release-0.5.1-1.el5.rf.*.rpm rpm -i rpmforge-release-0.5.1-1.el5.rf.*.rpm yum check-update

6. Install the ATrpms Repo. Create a new file /etc/yum.repos.d/ATrpms.repo with the following content:

   [atrpms-stable] name=Centos $releasever – $basearch – ATrpms baseurl=http://dl.atrpms.net/el$releasever-$basearch/atrpms/stable gpgkey=http://ATrpms.net/RPM-GPG-KEY.atrpms gpgcheck=1 enabled=1 includepkgs=libspf2* libsrs* [atrpms-testing] name=Centos $releasever – $basearch – ATrpms baseurl=http://dl.atrpms.net/el$releasever-$basearch/atrpms/testing gpgkey=http://ATrpms.net/RPM-GPG-KEY.atrpms gpgcheck=1 enabled=1 includepkgs=exim*

   Then run yum update. This will allow us to install exim-4.72 (which has DKIM) instead of the standard exim-4.63.
   #install the Apache httpd, PHP and Pear-DB

   yum install apache php php-pear-DB

7. Now install exim:

   yum install exim .... ================================================================================================================================================================ Package Arch Version Repository Size ================================================================================================================================================================ Installing: exim x86_64 4.72-41.el5 atrpms-testing 1.3 M Installing for dependencies: libspf2_2 x86_64 1.2.5-5.0.el5 atrpms-stable 49 k libsrs_alt1 x86_64 1.0-3_rc1.0.el5 atrpms-stable 12 k mysql x86_64 5.0.77-4.el5_5.3 updates 4.8 M postgresql-libs x86_64 8.1.21-1.el5_5.1 updates 196 k Transaction Summary ================================================================================================================================================================ Install 5 Package(s) Upgrade 0 Package(s) Total download size: 6.3 M Is this ok [y/N]: y Downloading Packages: (1/5): libsrs_alt1-1.0-3_rc1.0.el5.x86_64.rpm | 12 kB 00:00 (2/5): libspf2_2-1.2.5-5.0.el5.x86_64.rpm | 49 kB 00:00 (3/5): postgresql-libs-8.1.21-1.el5_5.1.x86_64.rpm | 196 kB 00:00 (4/5): exim-4.72-41.el5.x86_64.rpm | 1.3 MB 00:00 (5/5): mysql-5.0.77-4.el5_5.3.x86_64.rpm | 4.8 MB 00:00 ----------------------------------------------------------------------------------------------------------------------------------------------------------------