Why You Should be Running VIOS 3.x
Technical Editor Rob McNelly explains the advantages of upgrading your VIO server.
By Rob McNelly11/02/2020
The PowerVM® Virtual I/O Server (VIOS) provides the capability to virtualize your POWER® servers. It’s the software layer that runs between client VMs and the physical hardware.
Imagine a server running 25 VMs. Prior to the advent of virtualization, these would by necessity be multiple physical servers, each with its own set of network and SAN adapters. Of course, virtualizing physical hardware and sharing that among multiple VMs has obvious benefits. For starters, you eliminate the need for all of those extra boxes while having even greater power and capacity. Beyond that, there’s little need to dedicate a physical adapter to every workload because adapters can be shared most of the time.
VIOS debuted with IBM POWER5 servers running AIX® and Linux® workloads. With the availability of POWER6, IBM i workloads were also supported. Through the years, many administrators have come to rely on VIOS, but not everyone is using the latest versions. VIOS 3.1.0 debuted in November 2018, and the latest update, VIOS 3.1.1, arrived a year ago.
Now Is the Time to Upgrade
However, if you have yet to move to VIOS 3.x, you should do so as soon as possible. With Release 2.2.6 reaching end of life as of October, VIOS 2.x versions are no longer supported without an extended support contract. And continuing to use a release that’s out of support can put your organization at risk.
Maintaining access to IBM support isn’t the only reason you should be running VIOS 3.x on your servers. It’s important to understand that the latest versions of VIOS are fundamentally different from their 2.x predecessors. One important change is that VIOS 3.x is based on AIX 7.2, whereas VIOS 2.x was based on AIX 6.1. Just as there are advantages to running AIX 7.2 over AIX 6.1, there are advantages to running VIOS 3.x over VIOS 2.x. Most significant is that newer POWER hardware can be better exploited with AIX 7.2—and by extension, the virtualization code that comes with VIOS 3.x. The code base is cleaner, because IBM removed older unused packages.
These changes to the underpinnings of VIOS have necessitated a transformation of the upgrade process. While I wouldn’t say upgrading to VIOS 3.x is more technically difficult than what you’re accustomed to with 2.x, it must be approached carefully. This is something new that requires planning and preparation.
IBM has developed a viosupgrade tool, and I recommend practicing with it before upgrading your production machines. If you have spare computing capacity, it may make sense to use live partition mobility to evacuate your frames and perform the work on “empty” POWER frames so that running workloads aren’t affected. The upgrade process should be documented, and you should go in with the expectation that physical to virtual mappings, performance settings and more will need to be verified once you’re done.
While a complete explanation of the upgrade process is beyond the scope of this article, detailed information is available online (see “Upgrading Resources,” below).
And fortunately, you’re not on your own. Your business partner or IBM Systems Lab Services can help you scope out different options. In fact, this may be a good catalyst to examine your entire environment. Is VIOS 3.x supported on the hardware you’re running? Is your HMC in need of an update? How about your system firmware, or your AIX versions? If these different components haven’t been maintained, this project can and perhaps should mushroom into something well beyond a VIOS upgrade. You may even consider upgrading your hardware, as it may be easier to configure new hardware and install VIO 3.x from scratch while migrating your AIX workloads and decommissioning older hardware.
Rob McNelly is a senior AIX solutions architect doing pre-sales and post-sales support for IBM Premier Business Partner Meridian IT Inc.