IBM i 7.1 Tech Refresh Sports Live Partition Mobility
April 30, 2012 Timothy Prickett Morgan
As The Four Hundred told you months ago, IBM was indeed working on a Technology Refresh update for its IBM i operating system for the spring and this update does indeed include live partition mobility, bringing the IBM i platform up to the same level of logical partition live migration that AIX and Linux on Power have had for years. The Tech Refresh also includes a number of other enhancements to the integrated DB2 for i database, a repackaging of the DB2 Web Query tool, and a number of other tweaks and changes.
The Technology Refresh mechanism that Big Blue announced with IBM i 7.1 is akin to the Technology Releases it offers for its AIX operating system, although they are slightly different. The idea is to be able to change things down below the machine interface layer, perhaps providing support for a new processor or a new disk controller or network interface card–without having to go through a big operating system release and qualification cycle.
The march of the IBM i 7.1 Technology Refreshes.
Strictly speaking, a number of enhancements that IBM made to the IBM i stack last week in announcement letter 212-114 are not part of the Technology Refresh 4 (or TR4 in the new IBM lingo), but rather are part of a normal update of the IBM i platform, which includes a whole lot of features and functions that run atop this machine interface layer. The main thing to bear in mind is that IBM continues to make enhancements to IBM i, and it is doing so through mechanisms that are better than block-buster (and sometimes code-buster) releases and versions.
Live Partition Mobility, which allows a running logical partition to be moved from one physical machine to another one, is as much a feature of the PowerVM hypervisor as it is the IBM i operating system, and given the eccentricities of the OS/400 and i platform in terms of how it creates a single-level of storage for main memory and disk drives (among other issues), implementing live migration, as this feature is more generically called in the server racket, has been tricky. And, quite frankly, IBM was dragging its feet on live migration because it simply did not believe that customers needed it. Well, in a cloudy world, live migration is the ante to play the game, and the good news is that IBM realized that IBM i was not on par with AIX and Linux on Power Systems iron or with Windows and Linux on X86 iron and did something about it. Better late than never, and I am sure IBM would argue that it was pacing itself to the market requirements. I would argue–and have argued–that one of the reasons why the OS/400 and IBM i platform has not been able to go truly cloudy–which means something different then running in a hosted environment–is because live migration was not available. You can’t burst to a public cloud or move workloads within a public or private cloud without live migration. At least not in the easy and seamless way that all of the other major operating system platforms have.
There is a pretty long list of requirements to use Live Partition Mobility, and the first one is that you have to be using the top-end PowerVM Enterprise Edition hypervisor from IBM. Express or Standard Edition cannot offer this functionality. This is true for AIX and Linux as well, so IBM i is not being singled out or anything like that.
All of the prerequisites for the IBM i variant of Live Partition Mobility are at IBM’s developerWorks site here. So read very carefully before taking the plunge. You will need Power7-based servers on both sides of the live migration, and you will have to be at firmware levels 730_xx, 740_xx, or later, which are expected to be updated around May 25. You need the machines to be running PowerVM Enterprise Edition and to be using the Virtual I/O Server at the 188.8.131.52 level to virtualize all of the network and disk I/O for the partitions. The partitions obviously need to be at the IBM i 7.1 TR4 level, too. You can only use external storage arrays and the source and target machines involved in the live migration have to both be attached to the same array. The reason why is simple: a logical partition is just a big wonking file stored on an array with its running bits stored in main memory. When you want to do a live migration, you take a snapshot of what is in main memory and hold it for a microsecond and then beam it over to the target machine while at the same time changing the disk pointers for the LPAR on the target machine to the pointers that were used on the source machine. If the target partition has the same data in main memory as the source partition and is now in charge of the disk and memory. The migration takes a few seconds, provided your networks and your storage is fast enough.
The TR4 update also includes support for new solid state drives, a new SAS adapter for SSDs, a new four-port Gigabit Ethernet card, and a USB-attached DAT160 tape drive.
Allison Butterill, the new IBM i product offering manager (replacing Ian Jarman, who has filled that role for a long time), walked me through the IBM i 7.1 revamp, which also includes some other new features. Among these are some new XML enhancements for the DB2 for i database, which includes a new XMLTABLE function that allows users to query XML data stored in DB2 for i without having to first shred the document into database tables or host variables. DB2 for i in the 7.1 release (once the appropriate patches are applied) has extended three-part name support and other features, which we will explore in the coming weeks.
IBM has also repackaged the DB2 Web Query tool into a Standard Edition and an Enterprise Edition and shifted to the core-based pricing that is consistent with the way other IBM i, AIX, Linux, and systems software (like the PowerVM hypervisor) is priced. Under the old DB2 Web Query, you paid for a combination of different functions and users and this was far too complicated for both IBM and IBM i shops alike.
In response to a big request from COMMON and some large IBM i shops and ISVs, IBM is also announcing Application Management Toolset for i, in announcement letter 212-094. In a lot of cases, explains Butterill, developers working on in-house programs or ISVs writing code they hope to sell to IBM i shops use some of the system management functions of Programming Development Manager (PDM) and Source Entry Utility (SEU), which are part of Rational Developer for Power and have been part of the AS/400 stack forever. With this subset of these tools, you can edit CL routines and browse, move, filter, and manipulate objects. So now you don’t need to buy the full-on Rational tool if this is all you need to do.
Another big change–and one that shows that Software Group recognizes and respects the uniqueness of the IBM i platform–is the advent of what IBM is calling Workload Group pricing for IBM i. Basically, because you can pin a certain number of cores to a particular piece of software inside of an IBM i subsystem–even a bare metal machine that is not using the PowerVM hypervisor–Software Group is now optionally allowing customers to only pay for its entire software portfolio for the IBM i platform based on how many cores they use in a subsystem. In many cases, companies put a mix of IBM software inside a logical partition, and up until now, they had to license the software based on the full core count within that LPAR, even if the software never was going to use all the cores in the partition.
This is a good and fair change. It remains to be seen if ISVs will follow IBM’s suit, or if Big Blue will do the same for its analogous workload partitions (WPARs) for the AIX platform. WPARs are not quite the same thing as subsystems, but they are close and you can sure bet that AIX shops will want a similar deal.
The Workload Group pricing is available now. The IBM i 7.1 Tech Refresh 4 and other updates to the IBM i stack that you get through other PTF patches will be available on May 18.