Page 267 -
P. 267

238
                238   P P a r t   V :  a r t   V :    T T h e   G r e e n i n g   P r o c e s sh e   G r e e n i n g   P r o c e s s


                         But it’s a different story for more complex services, including the following:

                          •  Microsoft Exchange Server
                          •  Microsoft SQL
                          •  MySQL
                         These servers are more complex to cluster, and although it’s a good idea to have
                      redundancy in place, if one server goes down, it could take several minutes for the new
                      server to be transitioned to. This isn’t a virtualization issue; instead, it has to do with
                      various implementations of clustering software, the complexity of the server, and even
                      the application software.
                         These servers can be virtualized, however, if the service is transferred to a secondary
                      physical server. But for it to work properly, the memory must be constantly synchronized so
                      a switchover will be unnoticeable to users.

                 Server Virtualization Solutions

                      Server virtualization has picked up steam in the past few years, and plenty of companies
                      are offering their own solutions. In this section, we’ll take a look at two of the most
                      prevalent companies—VMware and Microsoft—and talk about their solutions.

                      VMware Infrastructure 3
                      VMware is the big dog on the virtualization block. The company offers a number of
                      applications for various virtualization needs and enhancements. Its flagship offering, however,
                      is VMware Infrastructure 3. The suite comes in three editions: Starter, Standard, and Enterprise.
                      Link 12-1 will get you over to VMware’s server virtualization section of the VMWare website.
                         Let’s take a look at the components and technologies in VMware Infrastructure 3.

                      VMware ESX Server
                      ESX Server is a virtualization layer that abstracts processor, memory, storage, and networking
                      resources into multiple virtual machines. It virtualizes server storage and networking,
                      allowing multiple applications to run in virtual machines on the same physical server.
                         ESX Server is also available as ESX Server 3i, which offers the same functionality as
                      the original ESX Server, but with only a 32MB footprint.
                      VMware VMFS
                      The file system at the heart of VMware Infrastructure is the VMware Virtual Machine File
                      System (VMFS). It is a high-performance cluster file system that allows multiple installations
                      of ESX Server to access the same virtual image. This technology makes it possible for multiple
                      users to access the same server image simultaneously.

                      VMware Virtual SMP
                      Processing performance is enhanced by VMware Virtual Symmetric Multi-Processing (SMP)
                      technology. This allows a single machine to use multiple processors simultaneously.

                      VMware VirtualCenter
                      Management of the suite is done through VMware VirtualCenter. This provides centralized
                      management, operational automation, and resource optimization to IT environments.
   262   263   264   265   266   267   268   269   270   271   272