While attending the IBM Power Systems Symposium this week, I learnt that starting with AIX 7.1 (and AIX 6.1 TL6) JFS2 logging is disabled during a mksysb restore. You may be familiar with disabling JFS2 logs, if not, take a look at this IBM technical note:   https://www-304.ibm.com/support/docview.wss?uid=isg3T1012643   I’ve been unable to find any official documentation from IBM that mentions this new enhancement to the mksysb restore process. However, when I checked my own AIX 7.1 system I found the following statement/code in the... [More]

Tags:  mksysb log=null disabled logging jfs2 chris aix gibson

Interested in paid support for LPAR2RRD tool?   Let’s all support Pavel and spread the word!   From: Pavel Hampl < pavel.hampl@cz.ibm.com > Date: 21 July 2011 3:00:19 AM AEST To: undisclosed-recipients:; Subject: LPAR2RRD professional support announcement Hi Everyone, You are receiving that mail because we have been either in touch in regards of LPA2RRD tool about year ago or you are on LPAR2RRD mailing list. I’ve decided to make professional paid support of LPAR2RRD. Here are my reasons which led me to that thought: - I have not... [More]

Tags:  lpar2rrd chris aix gibson

If you have the AIX iSCSI Software Initiator (iscsi0) configured on your system, you may find that nmon reports some “funny” information under the Disk Adapter (a) and Disk I/O (d) screens, such as:   ┌─topas_nmon──4=Top-by-RAM-use───Host=aix1 Refresh=2 secs───15:09.41──────────────────────────┐ │ Disk-Adapter-I/O ─────────────────────────────────────────────────────────────────────────────────────│ │Name          %busy     read    write        xfers Disks Adapter-Type                                  │ │vscsi1          0.0     ... [More]

Tags:  i/o iscsi iscsi0 aix nmon adapter stats disk

    IBM recently announced some significant changes to their ‘AIX Release and Service Delivery’ strategy. Starting February 2011, the following changes will apply for both AIX 6 and AIX 7.                 •           Three years of support for each Technology Level (TL). •           A single Technology Level per AIX version, per year. •           Service Packs will be released approximately 4 times per year per Technology Level.   Some of the benefits of the new strategy are:   Longer support for Technology Levels. –       More... [More]

A colleague of mine contacted me during the week to ask how one could determine if a POWER7 system was capable of Active Memory Expansion. I thought I'd share my response with everyone who follows my blog.   You can check if the system is capable of providing Active Memory Expansion (AME), from the HMC command line using the lssyscfg command, as shown here:   hscroot@hmc1:~> lssyscfg -r sys -m Server-8233-E8B-SN1000 -F active_mem_expansion_capable 1 Alternatively you can view the capabilities of the managed system from the HMC GUI,... [More]

Tags:  ame gibson power7 sap lparstat hmc memory chris amepat expansion active aix lssyscfg

If you are a system administrator that is responsible for managing AIX systems that run SAP, then you’ve probably had an experience similar to the following?   OK, so one day my SAP Basis administrator contacts me and says “ I can’t start saposcol ......can you please reboot the system? ” I quickly reply, “ Was there an error message when trying to restart saposcol ?”. He replies, “ No ”. Again I return very quickly, “ OK, have you checked to see if there are any shared memory segments left for saposcol? ”.   Just as quick, he replies “... [More]

Tags:  aix ipcs ipcrm memory gibson chris shared saposcol

The nohup command in AIX has the ability to “nohup” an existing process and protect if from hangup signals. Using the -p flag, an existing, running process can be “nohup’ed” and told to ignore SIGHUPs.   "Why is this useful?" I hear you ask.   Well, I'll often start a "long running" process on a system at work, like a backup for instance.  I'll sometimes forget to use the nohup command, so that my long running job will ignore any SIGHUPs and continue running, say for example if my ssh session to the server dies. The nohup... [More]

Tags:  nohup gibson aix chris

Just the other day, I needed to use the AIX splitvg command in order to copy some data from one system to another. I thought I’d share the experience here. The splitvg command can split a single mirror copy of a fully mirrored volume group into a separate “snapshot” volume group. From the man page: The original volume group VGname will stop using the disks that are now part of the snapshot volume group SnapVGname. Both volume groups will keep track of the writes within the volume group so that when the snapshot volume group is rejoined with the... [More]

Tags:  aix lvm

  Upon reading through the release notes for Fix Pack 22 for VIOS 2.1 , I stumbled across a new command called chkdev . According to the notes, this command was “ added to help you check devices for virtual provisioning capability ”. This fired my curiosity and as soon as I had applied FP22 to one of my VIOS, I started using this command to see what it could do for me!    First, I checked the man page for chkdev . It stated that chkdev can determine whether or not a device can be used in physical to virtual (p2v) migration on a VIOS.   chkdev... [More]