Server Consolidation Guide via Virtualization

sunshineluv7 writes to tell us TechTarget is running a good overview of 'why, when, and how to use virtualization technologies to consolidate server workloads.' The summary provides links to several podcasts and other articles relating real world experience with how to utilize virtualization to best meet your needs. From the summary: "Advances in 64-bit computing are just one reason that IT managers are taking a hard look at virtualization technologies outside the confines of the traditional data center, says Jan Stafford, senior editor of SearchServerVirtualization.com."

what sort of virtualization?

[Anonymous Coward]

When they talk "virtualization", do they mean running virtual domain service or virtual ips, allowing one computer to handle multiple web services, or do they mean running multiple virtual machines on one box?

I'm not too sanguine about the virtual machine approach. I suppose the only reason they'd be doing it that way is so that one server could seem like it's being multiple computers, so later the tasks can be split up if loads become high, or so that it looks absolutely identical to a two-machine setup that's being replaced. But while running virtual machines on x86-descended hardware has become much easier compared with only a few years ago, it still exacts a price in resources and performance, and may complicate administration. I'd strongly recommend using other techniques to load two tasks onto one machine.

For instance, let's say you want to run two SQL databases on one machine. The easiest solution is to partition the table namespace and run a single server. If the namespaces collide and there's no easy fix for it, you can run them on different ports and let iptables direct communications to one or the other based on ip.

I suppose there's one more reason for virtualization, and that's if you need to run multiple operating systems; but still IMO for future administration you're best off standardizing on one OS rather than trying to run two or more on the same box.

Re:64bit?

[afidel]

With PAE you could already give each virtual server 4GB to play with up to 64GB total with Windows 2003 Enterprise or 128GB with Datacenter. Linux 2.6 allows up to 64GB through the HIGHMEM_64G flag, all on standard x86 of P2 or later vintage (PPro had rudimentry PAE but implementing it was very hackish)