Shared Storage Pools - Migrating to New Disk Subsystem
I got this interesting question from Andrew Bielecki ( BieleckiAP 060000HJ8U ) from a different blog entry: I have 10 VIO servers with 16TB storage pool (16 x 1TB LUNs) on EMC VNX storage which we want to migrate to EMC VMAX3. What would be the best way to migrate this pool? Should we add 16 LUNs from VMAX3 and remove 16 LUNs from VNX or should we use failgrp command and mirror pool on VNX to VMAX3? It is a good question as there are many ways to do this operation and you are thinking of two good ones. The actual underlying disks subsystems... [More]
|
AIX and VIOS Min/Recommended Levels for POWER8 Hardware
Note: For the POWER7/7+ equivalent Blog take this link AIX and VIOS Minimum Levels for POWER7 and 7+ Hardware from 2013. UPDATE: January 2017 This information has aged in the last year and POWER8 has matured. Take this link for the updated information -> AIX, VIOS, System Firmware of HMC - Don't run anything over 2 years old
Below is now out of date: Note the latest and recommended versions will change... [More]
|
Shared Storage Pool - Best Practice & FAQ
I have been asked a couple of times for something like this for Shared Storage Pools (SSP) and I don't know of an official Best Practice and FAQ so here goes. This will always be a work in progress and covers new SSP releases as new features arrive - last updated March 2017 - NEW I have had loads of input/ from the VIOS SSP developers too, so its not just my thoughts and jokes!! If you have a question or a good tip or suggestion PLEASE: make a comment and I will include it. Shared Storage Pool - Best Practice and FAQ... [More]
|
Shared Storage Pools 6 Cheat Sheet
Here are my notes of the Shared Storage Pools commands that you need to remember. I have said it before but SSP is big on concepts and system admin time saving but very simple to operate. Updated Oct 2017 look for the NEW bits Creating the pool (once only) by example: Assumption: 1 GB Repository disk = hdisk15 and Pool data disks = hdisk7 to hdisk14, cluster and pool both called "alpha" Assumption: IBM V7000 A has LUNs: hdisk7 hdisk8 hisk9 hdisk10 Assumption: IBM V7000 B has LUNs: hdisk11 hdisk12 hisk13... [More]
|
HMC 8.2 Restricted Shell Window: Increasing the Font Size
This Blog is brought to you by Clive Benjamin (Principal Engineer) who worked out how to do it. If your HMC has a quality high resolution local screen or KVM screen then the Restricted Shell terminal window font size is far too small to read and the font used very narrow lines - in our humble opinion . This blog shows you how to fix this and "no", the obvious window Font Size option does not work. 1) Below: On the HMC start the Restricted Shell window 2) Below: With the cursor on the terminal window used Control + Right mouse button... [More]
|
VIOS Shared Storage Pool Single Repository Disk = Not a Problem
Odd. I thought I have put this on this blog before but I can find it now so just in case ... here it is or here it is again. The SSP4 can have mirrored failure group FC disks to handle adapter, FC cable, FC switch, entire FC disk sub-system, site or VIOS failure. But there is still a single SSP Repository disk. Isn't this a single point of failure? The answer is " No because you can quickly rebuild the contents of the Repository Disk after it has failed ." You are not meant to know this as it is internal to the VIOS... [More]
|
Fun with Fedora 20 Linux on POWER*
I was told that Fedora's latest build for the Power ppc64 processor would support SMT=8 , if you "err ... um" have machine with a processor that support that SMT=8 !!! This is not an announcement. So I gave it ago - here is my report: Getting Ready And I can't help thinking PowerVC would remove all this work, once the new version arrives that support my ... umm err! new machine!! Update I can tell you know that this was a POWER8 S824 machine as it is now available. Also Fedora 20 does not... [More]
Tags:  ppc64 fedora |
POWER8 - Why?
Inspired by this TED Talks Video on Leadership TED Talk by Simon Sinek Topic: How Great Leaders Inspire Action 18 minutes long http://www.ted.com/talks/simon_sinek_how_great_leaders_inspire_action.html It tells us to start with Why? To win hearts and minds. And not explain What? or How? until the Why? is very clear. I thought I would make an attempt: Why POWER8? We believe server sprawl means a future in which we drown in small computers taking 80% of the worlds electricity to run their idle loops 80% of the time. We believe we have got... [More]
|
The Linux on Power Advantage - Depends where you are coming from
Please provide comments on this blog entry - I want to know where I have it wrong? With IBM's massive investment in Linux on Power my brain hurts trying to express the advantages. This is because the technology is excellent but the bits you want depend on where you are coming from. So I have tried to break out potential users in to various types. For the record I am an Ab Linux on POWER User type! A - Current AIX and POWER user Already understands the POWER infrastructure, AIX and/or IBM i and are adding a new operating system... [More]
|
Ten Things POWER Techies need to know from the IBM Announcements 8th Oct 2013
IBM announced lots of Power Systems software yesterday but the official announcements are pretty thin on the details. I have many Twitter tweets asking "What the heck does that all really mean?" and the official statements are marketing messages and not technical information like: How do you get that working? What are the pre-reqs? What are the actual commands? What does the Graphical User Interface look like? How does that help me as a System Admin person? How, in the 21st century, IBM can announce a... [More]
|
Core files filling important filesystems? Want email alerts about each core dump?
I got asked these questions recently and had to go look the subject up ... again! I seem to have forgotten some of the details and then I thought I would use some new features of AIX for the second part. In the distant past there was various way to stop core files being dumped in to the current working directory of the program that failed. In AIX 5.3, AIX 6 and 7, the "chcore" command does all the hard work for us by letting us Choose a specific directory for core files - which is best in it own filesystem so it can't... [More]
|
AIX and VIOS Minimum Levels for POWER7 and 7+ Hardware
A very nice chart from Richard Milton of IBM on the minimum levels for AIX and VIOS of Power7 and Power7+ hardware. Download as a PDF: AIX_Levels_on_POWER7_Hardware_2013_06_20.pdf We will try to update this as new machines arrive.
|
Sizing with rPerf but Don't Forget the Assumptions
POWER Relative Performance (rPerf) is often used as a way to approximate the expected difference in performance between two Power Systems servers. Although rPerf is a useful tool, it is important to understand the limitations of using rPerf to provide an estimate the performance of your specific workloads in your particular environment with a new server, First, rPerf numbers, like any published benchmark, represent the best case result when the application, configuration and system resources are all optimized -- factors that are likely not... [More]
Tags:  aix powervm rperf lpar sizing power7 |
YouTube for all your POWER, AIX, Systems Director, PowerSC, PowerVM Hands-On Videos
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]
Tags:  youtube systems power powersc aix vidoes powervm director |
Workload Partition (WPAR) - Sharing filesystem Global AIX to WPAR
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]
Tags:  - filesystem aix global workload sharing wpar partition power7 aix6 |
Local, Near & Far POWER7 Affinity Nine Conclusions
I thought I should summarise the long eleven part Local, Near & Far POWER7 Affinity series. 1) Placement: Find out the layout of your boxes CPU and RAM and if the RAM is evenly distributed across available DIMMs Find out the placement of your Virtual Machines (LPARs) with lssrad -av - or - topas -M 2) SMT4 : Expect POWER7 SMT4 CPU use to “look” different POWER5 & 6 have two equal threads POWER7 shuts down threads 3 & 4 and even thread 2 - when there is not enough processes running. 3) Entitlement : Only set minimum Entitlements,... [More]
Tags:  lpar aix hypervisor entitlement processor systems firmware power power7 powervm virtual |
mpstat -d and the undocumented stats
I just realised that I got help from the AIX developers to explain the output of the mpstat -d command for my POWER7 and Affinity Technical University sessions in Miami and Copenhagen that I never passed on to every one. In an earlier blog we examined some mpstat columns but skipped others. The nearly undocumented mpstat stats are: S0rd, S1rd, S2rd, S3rd, S4rdand S5rd. In the AIX manuals it states: S0rd = The percentage of thread re-dispatches
within the scheduling affinity domain 0.
And likewise for the other numbers - but what does... [More]
Tags:  power7 cpu affinity virtual logical physical |
Local, Near, Far part 11 - Why Local+Far on Lower End machines?
I have been wondering why the lower end POWER7 machines have local and far memory and not local and near. Perhaps you wondered too! Well at the Miami Power Technical University, I got to talk to Dr Joel Tendler (IBMer) and a POWER7 processor guru and put the question to him. He covered this sort of architectural topic in his presentation at the event and I learnt a lot in this area by listening to the "master". Below is some background and the explanation too. The POWER7 chips has two memory controllers for maximum performance but... [More]
Tags:  795 xyz 780 near systems aix memory ab 770 far power7 power local bus |
Virtual Fibre Channel for NPIV Requires Memory too!
N-Port Id Virtualisation (NPIV) and virtual Fibre Channel adapters - like high speed physical adapters (see an earlier blog) do require memory to operator at full speed. NPIV effectively turns the Virtual I/O Server (VIOS) into a kind of virtual SAN switch where packets are passed through with no changes from the physical adapter to the client Virtual Machine (LPAR). I found it very hard to find a recommendation in the documentation but was given a rule of thumb. As before it should be noted that starving the VIOS and the Hypervisor of... [More]
Tags:  thumb power7 of rule npiv adapters power aix virtual |
What is the savings of using WPARs over LPARs?
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]
Tags:  power7 lpar aix7 aix wpar 5.2 |
Visio Templates for IBM Hardware
The original 2007 AIXpert Blog Entry: "Looking for Visio templates? You can find them at: http://www.visiocafe.com/ibm.htm " However, newer templates are not been made available since. All requests for updates and public release have not been successful. Reading between the lines, I (Nigel) have come to the conclusion (this is not an official statement but guess work on my part) that the costs are just far too high to publicly release IBM's third party created templates without any understanding the number of people... [More]
Tags:  resources |
Shared Storage Pool Stuck or Down? Don't Panic - Raise a PMR
I have a few customers and IBMers tell me their Shared Storage Pool (SSP) failed to come up after some major disaster like Total network outage Total SAN outage Total site unexpected electrical power outage They then fiddle about and eventually, like hours or even days later, send me email. All I can say is I am sorry to hear about their issue, that I don't have that problems and I have had my share of electricity cuts (ironically while testing the uninterruptible power supply!). But I can offer some advice . . . The... [More]
|
nmon for AIX detects LPM & DLPAR Changes
It seems that not many nmon users know that nmon for AIX will detect and show on-screen or save to the nmon file many AIX events. That is the problem about being the nmon designer and developer for so many years - it is called expert blindness. It is totally obvious to me until a respected nmon user asks a question to which my initial reaction is how can you not know the answer to that ! It can detect these among a number of other events and record them: Live partition Mobility (LPM) where you move a running Logical Partition... [More]
|
OpenPOWER IBM S822LC for HPC Minsky - First Look
Due to IBM marketing deciding to have four machines with the same Hollywood name = S822LC - every one has given up on them. This blog is about the POWER8 Minsky machine. This is developed and manufactured by Wistron for IBM under the OpenPOWER program and sold as the IBM S822LC for High Performance Computing (HPC) . Unlike some of the other S822LC model the name is actually correct. This computer only makes sense to me if you have a configuration with the very high performance maths computation NVIDIA GPUs. It also has higher... [More]
|
SSP I/O Graphs via the HMC REST API Python code walkthrough
Note: this Python script creates HMC Sessions but does not log off so they build up over times - The solution to that is covers in a new AIXpertBlog here: Avoiding HMC REST API Session Logoff Issues The main AIXpert Blog that explained everything but the code can be found here: AIXpert Blog: Shared Storage Pool I/O Graphs via the HMC REST API Detailed Walk through of PCM_SSP.py version 23 Note: In is example code, simplicity is more important than... [More]
|
Shared Storage Pool I/O Graphs via the HMC REST API
This has been replace by better python programs you can find POWER8 Watts Temp SSP I/O from HMC REST API Version 2 Download of the code files is available :-) Python code walk through completed here AIXpert Blog: SSP I/O Graphs via the HMC REST API Python code walkthrough The HMC can support loads of statistics about the servers it controls at both the server level and the Virtual Machine level. This function has been available... [More]
|
PowerVC Pre-Capture Checklist
This is really a reminder to myself because I hate searching for this list on my laptop but please comment on anything you see that as missing. Here is my list of things to check or do to make a nice clean image Date, time correct Timezone correct IP address & full hostname OK Check the content of /etc/hosts and /etc/resolv.conf are as expected Remove junk files from /tmp etc. & old / large logs Also check / and /home for unwanted files AIX “errclean 0” to remove old error log that don't apply to the new deploy AIX... [More]
|
VIOS Shared Storage Pool phase 6 - New Readme Content
The VIOS Install Instructions and Readme files can be found here: http://www-01.ibm.com/support/docview.wss?uid=hpc1vios_home The new on 11th Nov 2016 VIOS release 2.2.5 with the first service pack is VIOS 2.2.5.10. The VIOS 2.2.5 Readme includes the Installation instructions can be found here: http://www-01.ibm.com/support/docview.wss?uid=hpc1vios-40ce3a66 In this we find the usual limits but also a few rules for this and the increased number of VIOS nodes. Please read the "Readme" in full. Here I will highlight the important... [More]
|
VIOS Shared Storage Pool phase 6 - New Features
UPDATE: The Official IBM VIOS 2.2.5 Shared Storage Pools (Phase 6) New Features Announcement arrives three weeks after GA but better late than never, right! You can find it at this URL: VIOS Shared Storage Pools (Phase 6) Announcement = the Official Version My Summary of the Important Features Available with VIOS 2.2.5 – Generally Available 11 th Nov 2016 1. SSP VIOS nodes from 16 to 24 – a normally 12 dual VIOS servers 2. Fully support the DeveloperWorks SSP Disaster... [More]
|
Computer Room Temperature Monitoring with a Raspberry Pi
Update in 2017: I had to rebuild my Raspberry Pi due to a failed MicroSD "disk" and followed these instructions again and found I had missed a step: As the root user add to the end of /boot/config.txt this line: dtoverlay=w1-gpio and reboot. I found the DS18B20 temperatue probes did NOT work if I installed the Ubuntu 16.04.02 server image downloaded from Ubuntu (it appears it is missing some feature I could not fathom) but the Ubuntu MATE 16.04.02 image from the Raspberry Pi website (it took me to... [More]
|