AIXpert Blog is about the AIX operating system from IBM running on POWER based machines called Power Systems and software related to it like IBM Systems Director, PowerVM for virtualisation and PowerSC for security plus performance monitoring and nmon
Time to correct a few assumptions and statements that I made a while back. Previously I said the POWER Hypervisor decides where to put a Virtual Machine (VM/LPAR) based on the Virtual Processor number (spreading factor). Well, apart from it nearly being right ... I was actually wrong! I got talking to one of these very impressive Hypervisor developers in Germany and he put me right. In most of my larger machines, I do what I think is fairly normal for creating an VM - like working with a CPU core to RAM ratio that my customers use, like 1... [More]
Finally, I found the time to try this new exciting feature and it was really simple to create and operate. I captured movie footage of my first attempt and it all worked (once I removed my spelling mistakes in commands). It only took two commands. So the technology has advanced concepts but it really easy to use, COOL! Some of the commands come with long option names like "-custername". A quick misquote from Star-Trek, never goes wrong: "It is UNIX Jim, but not as we know it!" One command to create my cluster,... [More]
I was just asked this question by customer and it got me thinking, Items I would include: WPAR takes seconds to create and LPARs minutes LPARs need setting VIOS LV or LUNs but WPARs add simpler NFS mount points, or can just use Global AIX diskspace options LPAR needs 512 to 1GB to boot AIX and a WPAR takes just ~60 MB (yes sixty megabytes) You can share application code say 1 GB in each and every LPAR (40 LPAR = 40 GB) or just one shared read-only copy for all WPARs 40 WPAR = 1 GB).This saves man-power in maintenance, disk space AND memory (if... [More]
Here is another question from that larger Power 7 machine customer. They have large Virtual Machines (Logical Partitions) and can't see all the CPUs on the screen. This is made worst by Power 7 machines - not a problem with the processors or machines but there are: So many CPUs on larger machines like Power 770/780 and the mighty Power 795 Then the new Simultaneous Multi-Threading (SMT) now means four threads per physical CPU (core). This means lots of physical CPUs and each has four logical CPUs. So what happens on the screen - you see a... [More]
We have had the Global Services offering "Performance Management for AIX" server for years (even decades) - it gets shorten to "PM for AIX" or "PM for Power Systems" which sounds like a "Prime Minister for the Electricity Board" to English people! Anyway, briefly this offers: PM collects local AIX stats and configuration details, then sends the information to IBM over a secure Internet link to be analysed. The results includes performance graphs, performance trends, config reports and warnings about... [More]
I regularly get asked a question like: I have 4 months of data from 25 machines and have to develop a Capacity Planning model to size these LPARs on to new machines but I am having problems with having so much data. What can you recommend? We need graphs of CPU compared to Entitlement CPU Physical CPU use Maximum real memory use Network MB/s Disk MB/s Disk IOPS Sometimes this data is needed as input in to the Workload Estimator tool or Server Consolidation tools. My standard response is: You now understand Performance Monitoring and... [More]
I have never really understood why I get peaks and troughs in nmon questions and urgent situations but July seems to be a peak and fortunately I was not at work for a large part of it. Performance and nmon Questions trend to come in three flavours: really dumb, genuine and mega-urgent critical lets blame the hardware. Let me give you a flavour of each type of question from the last month. Perhaps, reading these will let you avoid the same problem or at least let you learn "you are not alone". Really dumb "nmon has stopped... [More]
Just completed the move of the POWER and AIX Hands-on Movies to YouTube videos - after pruning we have 97 of them. This means you can watch them on your mobile Smartphone and Tablets in addition to your workstation/personal computer. You can find them all here:
YouTube look for my "Nigel Griffiths" Channel http://www.youtube.com/user/nigelargriffiths This should mean they are simpler to find, search for and view. During the transfer I pruned out a few of the older ones particular Systems 6.2 as we now have a set of Systems... [More]
In the past with the POWER7 and POWER7+ based machines at the lower end like the Power710 to Power740 Models, users had to shut down the whole machine to add, remove or replace an adapter safely. In fact, some machines would power off as you removed the lid. This is no longer the case with the whole POWER8 range including the Scale-Out Models like the S822 and S824. These machines do not have the blind swap cassettes which allow the adapters to be removed from the rear of the machine. So you must have the cable... [More]
The "lparstat" command shows the available physical processors in the shared CPU pool on a Power5 micropartitioned server. The lparstat command can be run from any logical partition that has enabled "Allow shared processor pool utilization authority" **. The following lparstat output shows 10 measurements taken at 5 second intervals. The size of the shared pool is 2 CPU's (psize). The available processors for each sample interval is shown under the "app" column. For example, first line under the app column shows 0.65 available processors. The... [More]
I asked Scott about a Redbook for the new VIOS functions for Shared Storage Pools and he told me that chapters had already been added to the current PowerVM Redbooks. I almost fell of the chair! I have been ignoring the regular Redbook update emails - but I guess I should pay more attention. So I took a look and found the Shared Storage Pools have chapters in two regular PowerVM Redbooks - note you have to download the most recent updates. IBM PowerVM Virtualization - Introduction and Configuration SG24-7940 IBM PowerVM Virtualization -... [More]
We have blogged on this really cool AIX 7 feature in the past - but here is my problem: Once I install the AIX 5.2 mksysb image in to the Workload Partition running on AIX7 it all works fine but ... then what can I show an audience to show off "AIX 5.2 running on top of AIX 7": I need a simple application that only runs on AIX 5.2 . Something simple enough that it does not take hours to install and hopefully that it is something visually interesting to see. I am told we can run Oracle 8 now including the kernel extension but its not... [More]
For Systems Director 6.2 supports Firefox 3.6, 3.5 and 3.0 - you have to be nuts to not be using 3.6 IMHO! Internet Explorer 7 or 8. See http://publib.boulder.ibm.com/infocenter/director/v6r2x/index.jsp?topic=/com.ibm.director.plan.helps.doc/fqm0_r_supported_web_browsers.html Unofficially, I find Google Chrome 12 works fine too. For Hardware Management Console (HMC) (I am assuming a recent HMC V7R7.3 level here) it supports (from the Power7 manuals) Internet Explorer 7 but says IE 8 is not supported - just tried this and the left hand menu got... [More]
Here's a new Redbook that provides a system administrator view of the technical differences and methods necessary to complete a successful migration from Solaris to AIX 5L based systems. It also appears to be a good general AIX admin reference. Solaris to AIX Migration: A Guide for System Administrators http://www.redbooks.ibm.com/abstracts/sg247245.html Other Redbooks in this category include AIX Reference for Solaris Administrators http://www.redbooks.ibm.com/abstracts/sg246584.html?Open AIX 5L Reference for HP-UX System Administrators... [More]
I got another WPAR question today: From the Global AIX, I can add a filesystem to /wpars/WPARname/directory so the WPAR has access but what if I don't want to have the filesystem mounted there in the Global AIX? For example: I have a Global AIX filesystem called /tools that I want to mount in to one or many WPARs and appear and /temp in the WPAR(s)? My first answer is well you can use NFS because I do that all the time and I am a heavy user of NFS - no jokes please. I use NFS heavily! If the NFS server exports the mount point for every... [More]
AIX 6.1 TL04 sp3 supports the new POWER7 machines like Power 750, 77 and 780, where CPUs can be run at slower speeds to reduce electrical energy use when not busy. This feature is switched on by Systems Director and the Active Energy Manager plugin which talks to the service processor to enables it. I like the "Dynamic Power Saving - Favour Performance" option. From the AIX end, the pmcycles command is used to find your current CPU frequency. Before switching on the energy saving: # pmcycles -M This machine runs at 3550 MHz - This... [More]
I am currently updating my AIX systems and AIX 7 TL2 with its first service pack is now available for download from ESS or IBM Entitlem Software Support to spell it out in full (http://www.ibm.com/servers/eserver/ess) for install media and FixCentral for updates (http://www-933.ibm.com/support/fixcentral/). While downloading the install media files I noticed there is a new Firefox for AIX available Firefox V3.6.25. This is a jump up from the previous one and I have had (in the past) a few annoying problems with Firefox on AIX Some weird issue... [More]
It has bee a long few weeks traveling to Dublin, Las Vegas, Slovenia, Germany and Sweden to give lots of presentations. Six Weeks and five countries and the expenses are piling up on my desk. I was presenting a core set of topics like POWER7+ announcement summary, VIOS Shared Storage Pools (SSP3), Workload Partitions (WPAR) and Versioned WPARs to run AIX 5.2 and AIX 5.3, quick introduction to PowerSC (security tools), a Techie "what you need to know about" Systems Director for AIX, and Quick Dips in to Active Memory Deduplication... [More]
Active Memory Deduplication was announcement on 12th October and available on 14th October but there has been a little confusion on: what you need, how you install it and run it and how it works? This blog will attempt to demystify this interesting new Power Systems feature. This is one of many features to reduce the memory foot print and so reduce costs for POWER and AIX logical partitions. So far we have: Workload Partitions - reduce the memory used by many copies of AIX to just one Global copy and applications installed at the Global... [More]
So I got asked, just as an example configuration which forces lots of workload per CPU: Given a 16 CPU POWER machine and a need to run 100 workloads, would I recommend 100 LPARs or 100 WPARs? In case you are not familiar with POWER technology: LPAR = Logical Partition used the PowerVM to split CPU, memory and I/O across multiple virtual machines (also called virtual servers). The I/O is handles by a special purpose LPAR called the Virtual I/O Server, which provides virtual network, virtual disks, virtual optical and virtual tape. Each LPAR has... [More]
Hi, I am preparing for a Power Systems Technical University in Las Vegas, USA and Lyon, France in October. I have a session with the title below and I am seeking feedback from technology guru's like yourselves. Which four of the below ten technologies do you think are "most likely to be normal in five years time"? Please comment on this AIXpert (see "Add a Comment" below) with your four top technologies. I will post the overall results as a graph in roughly two weeks time. Below here there should be a large image of the ten... [More]
HMC V5.2, released in February, allows you to configure call-home to IBM Service using Secure Socket Layer connections. For many customers, this is preferable to using the Internet VPN option. Here are instructions for configuring outbound communication using SSL: 1. Go to the Remote Support menu under Service Applications. 2. Select the Customize Outbound Connectivity task. 3. Connectivity options include Modem, Internet, Internet VPN and Pass-Through Systems. (Pass-Through Systems are i5/OS partitions.) For SSL connectivity, select the... [More]
Recently, I delivered a 7.5 hour Systems Director 6.3 Instructor lead demo at IBM Zurich - that gives us 25 more people ready to dive into using it. It is a very polished building and the IBM Forum is amazing and they even have IBM food :-) I had to take a second mortgage out on my house to pay for the taxi to the airport (fortunately they take a credit card) and I thought Norway was expensive until now! Anyway, when I got back to the UK, I decided to perform the Systems Director 6.3 to 6.3.1 update. You get Systems Director to update... [More]
Recently I was running the "lsmap -l" command and it output error messages that were less then useless at the end of the output: Command did not complete.
"Determine if backing device is a PV or LV or optical." was last subcommand run.
Command did not complete.
Determining device type failed. Command did not complete.
"Determine if backing device is a PV or LV or optical." was last subcommand run.
Command did not complete.
Determining device type failed. Command did not complete.
"Determine if backing... [More]
Active Memory Expansion (AME) can second in my Top Ten Technologies to be business as usual in the next few years from hundreds of votes world wide. It is available on Power7 machines with AIX 6.1 TL4 SP2 onwards and AIX 7, of course. This allows memory to look at lot bigger than it actually is - to allow more LPARs to be running on a machine or giving headroom for boosts performance. The usefulness of AME is all down to the Expansions Factor (EF) - which is based on the compression ratio achieved for memory pages. If the EF very low then you... [More]
In Advanced Technology Support (ATS), we like to think we know what we are doing. Then something catches us out and we think that we had better let every other Power Systems administrators know about this or there are going to be many horrified users out there and many complaints. Note this problem hit our combination of HMC, VIOS and machines - you might get lucky but don't risk it! Gareth Coates (my ATS partner) volunteered to perform the regular 6 month update of our systems but hit a BIG problem. He writes: This... [More]
I need you to help me settle an argument or rather lack of information. I am getting conflicting messages about whether these smaller Power7 machines use Local and Near or Local and Far memory. I documented what I thought was correct in the Part 1 of this series of blog's. Actually, there is not much difference as these machines have two tiers of memory like "on the chip" or "some where else" so the names are hardly vital but I would like my facts straight. Unfortunately, I don't have examples of these machines with more... [More]
Another good questions from a customer and my answer was simple: The PowerVM internal network on POWER machines operates just like a physical network. If two LPAR are on the same internal network and the root user puts the virtual adapter in to promiscuous mode then it can see all packets. Just like a physical network. If the two LPARs are on different internal networks then they can never see the other LPARs packets. Just like two physical networks. If two LPAR are on the same internal network but on different VLANs then they can never see... [More]
UPDATED: 30 JANUARY 2015 The IBM Official Technote can be found here http://www-01.ibm.com/support/docview.wss?uid=nas8N1020533 It clarifies the mean of the ASMI settings i.e. it is the number of adapter slots AND the specific slots AND a further bug only some settings work until the next firmware release. Even with the newer firmware my recommendation stands: Completely Switch OFF the I/O Adapter Enhanced Capacity feature as you install the machine as it needs a power off - Unless you are running Linux on POWER8 with dedicated physical... [More]
I have been running the nmon ( n igel's mon itor) for AIX project for 15 years now but I am still learning. I initially wrote it to help me run AIX 3.2 then AIX 4 benchmarks on RS/6000 machines as running the older "down the screen" and "line by line" tools like vmstat and iostat was driving me mad (literally making my eye hurt) and so using screen curses enabled the number to stop moving on the screen. nmon's second most important feature was to make graphing the results simpler as a graph includes the time dimension, it... [More]