Say Sayonara To The IBM i Integrated Server
August 21, 2023 Timothy Prickett Morgan
One of the neat things about the AS/400 platform and its progeny is that it takes integration seriously, even to the extent of wrapping the OS/400 and IBM i platform around competitive platforms to bring them into the fold. The File Serving I/O Processor (FSIOP), which became the Integrated Netfinity Server, which became the Integrated xSeries Server, which became the IBM i Integrated Server is a good example of this.
This integrated server approach brought a real, discrete, physical X86 server running Windows Server, OS/2, Novell NetWare, or SCO Unix under the skins of the AS/400 and IBM i Server. It was eventually extended with more recent IBM i Integrated Server Support to support coupling of IBM i systems with X86 iron running VMware’s ESXi hypervisor as well as the Hyper-V hypervisor built into Windows Server (in this case, culminating with support for Windows Server 2012.)
In the old days, this integration was done with a server card that plugged into the PCI or PCI-Express system bus and used that bus like other I/O processors to provide a link between the X86 and the AS/400 or IBM i machine running a CISC or PowerPC processor. Eventually, IBM deprecated this approach and moved to attaching external BladeCenter blade servers and external System x servers based on X86 processors from Intel and AMD.
We don’t know how pervasive the use of these tightly coupled X86 servers were, but it always made sense to use to make these X86 machines subservient to the OS/400 and IBM i engines in the datacenter. The mission critical applications tended to run on OS/400 and IBM i machines, with the X86 adjuncts, usually running Windows Server in recent years, playing an application serving role. Hybrid computing, as IBM was delivering with this architecture in the late 1990s, is not a new thing, even though you might think it was with all the talk of using the CXL protocol over the PCI-Express bus to link together CPUs to memory and to external accelerators such as GPUs and FPGAs. Big Blue was doing this long before it was cool – and with less capable interconnects at that.
The fact that the IBM i Integrated Server is dead was brought to our attention by a business partner who only noticed it because IBM updated a notice document relating to this fact on August 17. Before reaching out to us, this partner also did the due diligence and figured out that IBM i Integrated Server support was never put into IBM i 7.4 or IBM i 7.5 and that IBM i 7.3 – which was withdrawn from marketing in September 2022, which goes off standard support September 30 this year, and which begins its pricey extended support, possibly for three years, beyond that – was the last IBM i operating system to have the integrated X86 server functions.
To be honest, we didn’t even think about this as being an option anymore, and maybe you didn’t either. But we also know that many of you have older iron running and maybe you have some of these IxS cards or IxA adapter links to external X86 machines in your datacenter, and you need to know this is happening.
IBM was unequivocal in its statement:
“The IBM i Integrated Server solution has been stabilized and will only be supporting the hardware and operating system versions that are currently listed in the iSCSI Solution Guide.
- There are no new planned enhancements to the IBM i Integrated Server product.
- There are no plans to support any new System x hardware.
- There are no plans to support any non-IBM hardware.
- There are no plans to support any additional operating systems.
- There are no plans to support IBM i 7.3.”
With Linux being the predominant operating system that is used to create new applications – particularly data analytics and machine learning workloads, but certainly not limited to that – and with Linux running natively on Power iron since 1999 in logical partitions side-by-side with OS/400 and IBM i, it is no surprise at all that IBM is not all that interested in embedded X86 servers under the IBM i server skins or even tightly coupling them over the PCI-Express bus, even with the modern CXL protocol that is so much better than the iSCSI approach that has been used for the IxA adapters in the 2000 and 2010s. Moreover, with Ethernet and InfiniBand speeds at 400 Gb/sec and soon going mainstream with 800 Gb/sec speeds, there are ways to provide very fast links between an IBM i server and any other kind of server over more standard links without any explicit drivers from IBM inside the IBM i platform.
Still, we think that there is probably a way to build a clustered machine with IBM i systems at the center and X86 and maybe Arm or RISC-V servers tightly coupled to it and supported and run as a single machine for workloads that cannot be easily consolidated down to LPARs on a single big NUMA box. But in a lot of cases, it is probably more fruitful for IBM to focus on a mix of IBM i and Linux partitions that work in concert and that are easy to manage – and inexpensive. This is what has been successful – wildly successful, really – for the System z mainframe and what we think the Power Systems division could mimic successfully with a slight change in tactics.