Hi Francois
You must talk to your server administrators. It looks like they have mixed incompatible OpenSSH packages between CentOS and RHEL. Read this thread http://lists.centos.org/pipermail/centos/2011-February/106531.html.
That said, it is the SSH server daemon refusing to start. That shouldn't block Moodle which depends only on webserver (Apache) and the database server (MySQL).
You must talk to your server administrators. It looks like they have mixed incompatible OpenSSH packages between CentOS and RHEL. Read this thread http://lists.centos.org/pipermail/centos/2011-February/106531.html.
That said, it is the SSH server daemon refusing to start. That shouldn't block Moodle which depends only on webserver (Apache) and the database server (MySQL).