Red Hat has published Red Hat Enterprise Linux 5.7, the seventh major revision of RHEL 5, which was launched in March 2007. As with RHEL 6, which was introduced last autumn, series 5 is currently in the first of four lifecycle phases; the new version not only includes the bug fixes produced over the past few months, but also refreshed drivers, optimisations, and new features.
A few improvements to the KVM hypervisor in RHEL 5.7 are designed to improve the emulation of CD drives and solve problems related to the boot sequence. In addition, Red Hat has reduced the time needed for live migration, i.e. the shifting of guest systems between hosts on running machines.
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