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Linux Offers a Full Menu of Options

With Linux on Power becoming a priority for IBM, you should consider several things when looking at implementing Linux. One of the most important is cost. With multiple costs that must be understood, it’s sometimes difficult to navigate. Costs include hardware and hardware maintenance, software, software subscription and software support. On top of this is a somewhat confusing matrix of options. If you take a simple menu-based approach, it can simplify the decision process.

Appetizer (Hardware)

The first part to understand is where Linux can run in a Power environment. The answer is almost anywhere. Whether you have a Power or PowerLinux server, you can run RHEL or SUSE. The answer may be anywhere, but it’s not necessarily cost-effective to run it anywhere. You should carefully examine your environment to find where you can benefit from Linux on Power. Some places to look are unactivated capacity on enterprise-class servers, unused capacity on midrange servers or possibility adding capacity with dedicated servers.

Wherever you choose to run Linux, remember the difference between PowerLinux and Power servers. PowerLinux servers can only run Linux operating systems, while Power servers can run IBM i, AIX and Linux. You’ll also see pricing differences between the two. PowerLinux servers are priced competitively to contend directly with x86-based servers, while there’s a premium for Power servers as they have more flexibility. To bring that competitive pricing to enterprise Power servers, IBM introduced Power Integrated Facility for Linux (Power IFL). The Power IFL is a packaging of hardware activations and PowerVM software activations that consists of four processor-core activations, 32 GB memory activations, and four PowerVM for Linux licenses.

Main Course (Software, Support and Subscription)

Any delicious main-course menu offers a variety of options. With this main course, you’ll need to choose Linux distribution, size, and who and how it will be supported. The distribution may be the easiest depending if your enterprise has already chosen a direction. There are two main licensing differences between SUSE and Red Hat. The first is number of LPARs. SUSE lets you create unlimited LPARs with any license while Red Hat limits the number of LPARs depending on what type of license you purchase. The second difference is SUSE keeps costs consistent across Power and PowerLinux platforms while Red Hat offers a reduced license cost for PowerLinux servers. Both SUSE and Red Hat offer per-socket licensing.

After you’ve selected your distribution, your next choice is a little more difficult. Support and subscription are typically lumped together in the AIX and IBM i worlds. In the Linux world, they’re separate and have some options. Subscription is the capability to download updates and patches to the distribution you’re using. Subscription is only offered by the distribution vendor you’ve chosen and is typically sold in one- or three-year increments. Support is the capability to open trouble tickets on the distribution you’re using. You have a little more flexibility here. In addition to the distribution vendor selling support, IBM also sells support. The main difference between the vendor’s and IBM’s support is IBM’s support is server based while the vendor’s is socket based.

The final choice is to pick a support level. Each distribution offers a standard or premium support. Each vendor’s support will vary slightly, but in essence standard support is 9-5 and priority or premium is 24-7. This decision will be driven primarily by where in your environment theses LPARs will reside.

Dessert (Applications)

Another great advantage to running Linux on Power is running IBM software on the server. IBM has sweetened the pot and stated that any Power core running Linux OS needs 70 PVU of licensing. Depending on what the software is currently running on, this could be a significant savings. Let’s say for example, you’re currently running an IBM WebSphere environment on an AIX LPAR on a 770. This LPAR has an entitlement of four-core and requires 120 PVU of licensing per core. Using a made-up number of $50/PVU, the cost of licensing this environment would be $24K. Now, using the same example swapping out AIX for RHEL at 70 PVU, the cost to license the environment dramatically drops to $14K. That’s 41-percent savings. Now, imagine this magnified by the number of servers you have running!

Full Menu of Options

As you can see, several different options exist when you’re considering running Linux on Power, many of which can save you some money. These options also make running Linux on Power very competitive with other Linux platforms. The bottom line is to understand your options, on all platforms, before making your Linux decision.

Andrew Goade is an architect for Forsythe Technology Inc. He can be reached at



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