This article originally appeared in the December issue of Internet Telephony magazine.
Many of today’s applications rely on effective storage strategies to ensure that services behave in the manner intended and deliver the expected result to the end user. And yet few would argue that storage is a commodity and that there is little direct added value to the applications storage serves. In fact, many developers will tell you that the less intrusive storage is to the application, the better.
But, traditionally, storage has been directly tethered to the applications, or at least to the machines running those applications, using SCSI or fibre channel connections. This need for physical connectivity made it impossible to move storage away from the applications it served. The advent of iSCSI made it possible for devices to exchange SCSI commands via an IP network infrastructure, negating the need for a dedicated, physical connection between servers and storage. Unfortunately, early implementations of iSCSI suffered from a problematic lack of speed. While it was good for certain types of applications, anything requiring speeds of more than 1GB per second would suffer. All of that has changed with the advent of 10GB iSCSI.
So what? iSCSI is faster now, but can’t that argument be made about processors and other computing technology? However, it’s not that iSCSI is simply faster; rather it’s what you now can do because it’s faster. In the ATCA world, 10GB iSCSI opens the door for the deployment of stateless platforms that effectively separate the computing nodes from the disk. Your storage only holds data, while the “state” of the servers that make up the platform (OS, applications, etc.) is booted from a centralized or remote location. Upon boot, the state of the servers is loaded from this source and can then access the required stored data.
Final Score. What’s the benefit of going “stateless” in an ATCA platform? By separating the disk from the servers and centralizing the OS and application images, you create an environment perfect for easy upgrades and changes. Deploying new servers, or modifying the OS or applications doesn’t require data migration as in the past. This stateless approach also reduces management overhead by limiting the number of OS instances and app images that need to configured, upgraded and deployed in the event of a change. Further, this approach can lower the power consumption and total cost of ownership of ATCA blades by reducing the number of physical blades needed to achieve your goals.
Jeff Hudgins, Vice President of Engineering at NEI, writes the Tech Score column for TMCnet. To read more of Jeff’s articles, please visit his columnist page.
Edited by Greg Galitzine