RHEL 5.9 clones arrive from CentOS and Oracle
CentOS 5.9 and Oracle Linux 5.9 are now available. Both these Linux distributions are available free of charge and are based on the sources of Red Hat Enterprise Linux (RHEL) 5.9, which was released eight days ago and is only distributed by Red Hat to customers who have a service subscription. The two new distributions include all the new features that Red Hat has built into RHEL 5.9, for example OpenJDK 7, Samba 3.6 and the drivers for Microsoft's Hyper-V virtualisation software.
Oracle Linux 5.9 has so far only released updated packages; new ISO installation images will follow shortly. The CentOS project reached a similar point a few days ago.
Apart from some details that are negligible in terms of software compatibility, CentOS doesn't differ from its source; sometimes, the CentOS project even goes as far as deliberately leaving known bugs unfixed to ensure that CentOS remains fully compatible. Oracle makes a far greater number of changes and will, for example, incorporate corrections into its distribution's RHEL-based kernel; the release notes list various such differences from the original Linux 2.6.32-based kernel. Oracle also includes the "Quarterly Update 2" of its Linux 3.0.36-based Unbreakable Enterprise Kernel (UEK) 2; this kernel now supports AMD's "Abu Dhabi" processors and offers a Network Block Device (NBD) driver.
In parallel with the new RHEL clones, Mark J Cox has released the "Enterprise Linux 5.8 to 5.9 risk report" on Red Hat's security blog. In this report, the Red Hat employee analyses the security fixes that were released between 5.8 and 5.9. Cox says that Red Hat closed 332 holes with 101 patches; 16 of the updates were rated critical, 30 important. All critical updates affected three components: Samba, PHP and Firefox/XULRunner.