Virtualization on Solaris

Now that you’ve seen HP virtualization, take a closer look at Sun’s xVM, along with containers, hardware partitioning, and logical domains.

Sun made some bold changes in 2008, the most important being the release of xVM. Sun’s xVM is actually a mix of four separate technologies, the first of which was introduced in February of 2008: xVM Ops Center. xVM Ops Center’s most important function is that it provides a single console for the management of all devices in a virtualized environment. It further allows for the discovery and management of all physical and virtual assets. The other three technologies include the xVM server, VirtualBox, and VDI software. The xVM server is a hypervisor-based solution, which is based on Xen, running under Solaris on x86 computers. On SPARC it is still based on logical domains. Containers and LDOMs now are part of the umbrella named xVM.

New to Solaris in 2009

One new feature, introduced in the October 2008 update of Solaris, allows users to migrate workloads among Solaris systems and reduce the administrative overhead required to move containers between unlike configurations. This lets Solaris 8 and 9 containers run multiple Solaris 8 or 9 environments on one SPARC system. In an October 2009 release, their latest update, a new feature allows for parallel patch installation of virtual Solaris containers.

Sun is also claiming features such as predictive self-healing, which has long been available on the System p. VirtualBox is desktop virtualization software geared toward developers, allowing for many different types of operating systems to run on top of an existing desktop operating system. It supports Windows, Linux, Mac, and Solaris hosts. Sun did not develop this product, but acquired open source desktop virtualization vendor Innotel, which develops the product.

Sun also offers hardware partitioning, which allows their high-end servers to be divided into four-process partitions. These are referred to as Sun DSD’s. In many ways, this technology is similar to IBM’s logical partitioning, which was introduced in 2001, with no real virtualization capabilities. It is also similar to HP’s hardware partitioning in that only high-end and mid-range servers support this technology. You cannot share resources between partitions nor can you dynamically allocate processing resources between partitions. You also cannot share any I/O. It’s the LDOMs that actually allow virtualization. Introduced in 2007 on their SunFire line of servers, LDOMs enable customers to run multiple operating systems simultaneously. While LDOMs solved a huge deficiency in Sun’s virtualization strategy, it has many inherent flaws:

• Scalability — Only eight CPUs and 64 GB RAM on one machine
• Server-line — Only low-end Sparc servers are supported
• Limited micro-partitioning — Four partitions on T1, 8 on T2
• No dynamic allocation between partitions

For years, Sun’s answer to everything was containers or zones. Containers and zones give you the ability to run multiple virtual operating system instances inside only one kernel. They are used to provide an isolated and secure environment for running applications, which are created from a single instance of Solaris.

Simply put, they had it and IBM did not. Sun can no longer make this claim. IBM now offers AIX workload partitions (WPARs), which is their answer to containers. IBM WPARs have all the features of containers plus additional innovations:

• Application WPARS — A workload partition that allows a single process or application to run inside of it, like a wrapper. Unlike a standard WPAR, it is temporary and stops when the application ends.
• Live Application Mobility — This feature lets you move running WPARs to other partitions without any user disruption. With Solaris, you need to shut off the zone first. The feature also lets you perform multi-system workload balancing, which can be used to conserve data center costs.

While Sun appears to be moving in the right direction with xVM, it still needs to standardize its offerings more. There is still too much confusion around their offerings and virtualization roadmap. Nothing new has been announced in 2010 in the Sun world, unless you want to discuss Sun ending development of its 16-core UltraSPARC-RK processor.