The IT landscape has changed, and talk of the mainframe's benefits is again audible. The mainframe vs. server question comes down to space and facilities costs as well as simplicity of operations.
Remember the mainframe? A few decades ago, with the rise of client-server computing, everyone thought mainframes would quickly disappear from the data center. In the 1990s, when servers grouped in local networks stored files in a central location, there was no need to keep the expensive mainframe. For the price of one mainframe, you could afford to buy a hundred servers.
A mainframe is like one very large server that can do anything that multiple servers in a rack are able to do.
As the Internet took over, servers became more complex. Often, several servers had to work together to accomplish a specific task. Data centers grew to accommodate more and more servers, which demanded power and cooling resources. Some power providers increased capacity just for data centers, and electricity costs continued to rise. Virtualization and cloud computing trends have influenced the numbers, but server sprawl is still on the rise.
But the mainframe vs. server argument never really went away. And, to the surprise (or dismay) of many, mainframes might be winning the debate.
A large Midwestern U.S. security company replaced more than 200 servers with one big mainframe in 2012, according to the company's data center architect. "We save a fortune on electricity and the mainframe is doing everything our 200-plus servers were doing in the past. And we can reduce the size of the data center, which means that we can save an additional fortune on realty," he explained.
Next-generation mainframes can run an open operating system like Linux, eliminating the cost and inconvenience of proprietary OSes. Major Linux vendors like Red Hat and SUSE have a version of their distribution that runs on mainframe hardware.
"A mainframe is like one very large server that can do anything that multiple servers in a rack are able to do. It's a virtualization platform; its hardware is highly redundant, so it replaces a cluster of servers. And, compared to all the x64 servers, it's not even that expensive," said the data center architect.
Even if mainframes are a tough sell, it is clear that a comeback is in the works. Large companies can even save money on IT infrastructure by replacing hundreds of servers with one huge -- if expensive -- mainframe computer.
About the author:
Sander van Vugt is an independent trainer and consultant based in the Netherlands. He is an expert in Linux high availability, virtualization and performance. He has authored many books on Linux topics, including Beginning the Linux Command Line, Beginning Ubuntu LTS Server Administration and Pro Ubuntu Server Administration.
This was first published in July 2013