Edit: I still love Redbooks.
Originally posted August 14, 2012 on AIXchange
Occasionally I like to highlight IBM Redbooks that provide particularly valuable information to AIX pros. The new publication, “IBM PowerVM Best Practices,” is the latest example.
The version I viewed was a draft document (“Redpiece”) dated July 2, 2012. If it hasn’t yet been finalized, it should be soon. While a fairly short read at 118 pages, this publication is packed with relevant information that should be easily understood.
Chapter 1 notes
The authors remind us of the features and benefits of running PowerVM (section 1.1). Current VIO server minimums include 30GB of disk, a storage adapter, 768MB of memory and 0.1 processor (section 1.2). It’s worth repeating that that memory figure is a minimum. In fact, 6GB of memory and a core of entitled capacity for your VIOS is suggested (depending, of course, on your workload) in section 1.3.4.
The authors add: “Core speeds vary from system to system, and IBM is constantly improving the speed and efficiency of POWER processor cores and memory. Therefore, the above guidelines are, once again, a starting point. Once you have created your [VIOS] environment, including all the virtual clients, you should test and monitor it to make sure the assigned resources are appropriate to handle the load on the [VIOS].”
Section 1.3.7 addresses the question of whether to run a single VIOS or multiple VIO servers. The authors recommend the latter given the benefits of redundancy.
Section 1.3.9 covers slot numbering and naming conventions.
Chapter 2 notes
Installation, migration and configuration are covered. Included is a nicely documented section illustrating VIOS configuration on an HMC.
Two important reminders: First, set all physical adapters to desired, as setting them to required prevents dynamic LPAR (DLPAR) operations from working (section 2.1.4). Similarly, all virtual adapters should be set to desired if you’re planning on implementing live partition mobility (section 2.1.5).
The authors recommend using NIM to install the VIOS, citing this documentation.
Section 2.3.1 covers the need to perform regular maintenance. Firmware updates and patching should be done once a year. Two other points from the authors:
“When doing system firmware updates from one major release to another, always update the HMC to the latest available version first along with any mandatory HMC patches, then do the firmware. If the operating system is being updated as well, update the operating system first, then HMC code, and
lastly the system firmware.
“In a dual HMC configuration always update both HMCs in a single maintenance window, or disconnect one HMC until it is updated to the same level as the other HMC.”
Section 2.3.3 has a checklist you can use to apply fix packs, service packs, and ifixes. Section 2.4 covers VIOS migration.
Chapters 3 and 4 notes
Administration and maintenance are covered, including the process of backing up and restoring the VIOS (section 3.1). Backing up the VIOS is a separate task from backing up your client LPARs, so be sure you are backing up both (section 3.1.1). The VIOS should be backed up to a remote file (section 3.1.2).
Restoring the VIOS — from either the HMC or by using a NIM server — is discussed in section 3.1.4. In a D/R scenario, NIM is recommended (section 3.1.5).
Changes made with DLPAR operations should be saved by either manually making the changes to the profile, or by using save configuration from the HMC GUI (section 3.2)
Section 3.2.1 has a warning. This has actually tripped me up with NPIV in the past, so pay attention:
“Using the method of adding a virtual FC adapter to a virtual I/O client via a DLPAR operation, and then modifying the permanent partition profile, will result in a different pair of WWPNs between the active and saved partition profiles.
“When a virtual FC adapter is created for a virtual I/O client, a pair of unique WWPNs are assigned to this adapter by the Power Hypervisor. An attempt to add the same adapter at a later stage will result in the creation of another pair of unique WWPNs.
“When adding virtual FC adapters into a virtual I/O client via a DLPAR operation, use the ‘Overwrite existing profile’ option [Figure 3-4, page 44] to save over the permanent partition profile. This will result in the same pair of WWPNs in both the active and saved partition profiles.”
Section 3.3 covers the virtual media repository. Section 3.4 covers power server shutdown and startup.
Chapter four covers networking best practices, examining many different scenarios. You should read through them all.
There’s plenty more, so next week I’ll cover the rest of the material in this publication.