Last month I applied the latest fix pack for VIOS 2.1 i.e. FP22, to one of our lab VIOS. I came across the following error while doing so:    Renaming Media Repository Logical Volume:   VMLibrary_LV --> VMLibrary umount: error unmounting /dev/VMLibrary_LV: Device busy   Media Repository failed to unmount. We cannot continue until it can be successfully unmounted. Please address and retry.   update:   Failed while executing the ios.cli.rte.post_u script.   installp:   The installation has FAILED for the "root" part         of... [More]

  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]

I stumbled across this IBM support tech note today. It relates to controlling which network to use during a Live Partition Mobility operation.   http://www-01.ibm.com/support/docview.wss?uid=isg3T7000117&myns=phw&mynp=OCHW182&mync=E   By being given the choice of which network to use we can select network adapters that are more suited to this type of activity i.e. ones that are one or more of the following:  high-speed, under utilized and/or dedicated to non-application data (for example). Using a “high speed” network may... [More]

Recently a colleague contacted me with a question relating to hostname resolution and DNS on AIX 6.1. I thought it was an interesting discussion so I thought I’d share it with you here.   His question was basically this:   “I n AIX 6.1, as you know, the resolv.conf has some additional options. Do you know what would happen if I have two nameservers in my file and the target hostname isn't found, will the second nameserver necessarily be looked up? The man page says:   If more than one name server is listed, the resolver routines query... [More]

What are the considerations for paging devices when using Active Memory Sharing (AMS) with Live Partition Mobility (LPM)? Paging devices can only be assigned to one shared memory pool at a time. You cannot assign the same paging device to a shared memory pool on more than one system at the same time. If you accidentally assign a SAN paging device to both the source and destination VIOS, this can result in memory corruption.  When data is read from the paging device during the LPM operation or post-migration, when memory is accessed on the... [More]

Thanks to the IBM Virtual Loaner Program, I was able to try out my first POWER7 LPAR today.  Some interesting items for me to research.   # lparstat -i Node Name                                  : node1 Partition Name                             : node1 Partition Number                           : 5 Type                                       : Shared-SMT-4 Mode                                       : Uncapped Entitled Capacity                          : 0.50 Partition Group-ID                         : 32773 Shared Pool ID          ... [More]

Before migrating to AIX 6.1 you might want to check that ncargs is set to a value greater than or equal to 256 e.g. # chdev -l sys0 -a ncargs= 256   $ lsattr -El sys0 -a ncargs ncargs 256 ARG/ENV list size in 4K byte blocks True Let me elaborate. Recently we migrated our LPARs from AIX 5.3 to AIX 6.1. Our AIX 5.3 systems were migrating from 5300-07-05-0831 to AIX 6.1 at 6100-03-01-0921. During the testing of the migration process we noticed that some of the sys0 tunables were being reset to their default settings after the migration had... [More]

Came across the following IBM Wiki site which is dedicated to all things related to Live Partition Mobility (LPM) on IBMs Power6 (and Power7) platform.   http://www.ibm.com/developerworks/wikis/display/virtualization/Live+Partition+Mobility Lot's of really interesting and useful information regarding LPM. If you are planning on implementing LPM, or even if you are already using it, I recommend you take a look at this site. Cheers. 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

Today, IBM announced AIX version 7.   http://www-03.ibm.com/systems/power/software/aix/v71/preview.html Several new features were mentioned in the launch, but there were two new features that I found particularly interesting:   - AIX 5.2 WPARs for AIX 7 - Cluster Aware AIX   I thought I would briefly describe each feature in this post.   AIX 5.2 WPARs for AIX 7   In AIX version 7, administrators will now have the capability to create Workload Partitions (WPARs) that can run AIX 5.2, inside an AIX 7 operating system instance. This will... [More]

Back in 2008, VIOS version 1.5.2.1, Fix Pack 11.1 was released . A new command was introduced with this Fix Pack, called seastat.   This handy little utility can be used to view Shared Ethernet Adapter (SEA) statistics per virtual I/O client.   This is not to be confused with a certain shell script that Nigel Griffiths wrote a while back!   From the man page:   “The seastat command generates a report to view, per client, shared ethernet adapter statistics. To gather network statistics at a per-client level, advanced accounting can be... [More]

A quick tip for monitoring Multiple Shared Processor Pools with topas . Execute topas from the AIX command line. Press the ‘ p ’ key to toggle on ‘pool metrics’. You will see the default pool (pool id 0) and any other pools defined on your system. In the example below, there are two pools, the default (0) and a user defined pool (1). The default display shows the LPARs in the default pool (0), which in this case is sys06_partition8 .   Using the up and down arrow keys, I place the cursor on pool ID number one, in the pool column on the... [More]

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

Have you ever encountered this error message on AIX before?   # man -k loopmount man: 0703-310 file man not found. Create the whatis database using the <catman -w> command Of course you have! If you’ve ever installed AIX from scratch then you have undoubtedly seen this message.   And of course, you dutifully executed the ‘ catman –w ’ command to rectify the situation. Didn’t you? But what if   ‘ catman –w ’   doesn’t work as expected?   I recently came across this minor issue. Running catman produced the following error... [More]

Tags:  gibson whatis catman chris aix man