I don't really get the chance to update this blog (it has been over 12 months) however I did find something of interest this week while installing new Power7+ 750 machine.
One thing I wanted to evaluate was enabling Favour Performance mode with IBM EnergyScale.
Details of what it is and how it works can be found here:
From the HMC launch the ASM, select system configuration, power management, power mode setup and select “Enable... [More]
We have a number of clients who have a single AIX server in their environment. There is no NIM server, and no other AIX system to send mksysb backups to. One way of backing up the system is to use a backup to a local tape drive, or a DVD drive. This is fine until you want to use some backup software to take care of the backups for you. This will do a great job of backing up any applications or files on the AIX system, however there is some capability in backup products to backup the operating system (eg/ Tivoli Storage Manager for system backup... [More]
One question I have been asked latley is how to replicate an AIX system's rootvg to another AIX system using storage system replication. Can I just boot from the rootvg LUN on another system? Well... unfortunately it's not as simple as just remote mirroring the rootvg and booting off it at the DR site. This will work, but it's not a good idea, and I'm not sure if it's exactly supported. For the non-rootvg disks that is simple, you can just replicate them via your storage system, and in a DR map the target volumes (or a snapshot of them) to the... [More]
This week I found that after updating our HMC and VIOS our VIO mksysb (backupios) backups started failing. Our HMC is on 7.7.3 HMC code. Our VIOS is on 18.104.22.168 code. The mksysb backups are scripted from our NIM server, where we do the following to perform the backup: - Setup SSH keys to the HMC - Mount our /export/nim/mksysb filesystem on the VIO server as /mksysb - Run the "viosvrcmd" command on the HMC to run the "backupios" command on each VIO server - Define the mksysb backup as a NIM resource - Un-mount the NFS... [More]
As part of an LVM migration to new storage, we found that our mksysb's started failing. This was also our NIM master which held mksysb images for all the LPARs in our environment so this needed to be fixed quickly. We used unmirrorvg and mirrorvg to migate to the new disks, for example moving our rootvg from hdiskY to hdiskX: # extendvg rootvg hdiskX # mirrorvg -S -m rootvg hdiskX # bosboot -ad hdiskX # bootlist -m normal hdiskX # unmirrorvg rootvg hdiskY # reducevg rootvg hdiskY # rmdev -dl hdiskY After this was done, we saw the below error... [More]
From PowerHA 7.1.1 you are able to replace the CAA repository disk to another disk. This would really only be used if you lost access to whatever reason to the LUN that is used for the CAA repository. As part of testing a cluster build, it is worthwhile testing that the CAA disk can be moved to another LUN without issue. I ran through the steps on my cluster in the office, and everything worked ok. First, check the cluster level: root@ha71_node1:/home/root # halevel -s 7.1.1 SP1 I am going to replace hdisk50 (existing repository disk)... [More]
In a number of situations you would have an NFS filesystem that you would allow a number of hosts root access to. A simple example of this is an NFS mount with all of your install media. You would then export the filesystem, and specify all the hosts that are allowed root access. In the case of an AIX environemnt I have been working on, I had a number of LPARs on a single system, with a private network setup for backups, and for the LPARs to communicate without going outside of the POWER7 frame. When I added new LPARs, I didn't want to have... [More]
In the case that you have a PowerHA cluster that contains multiple resource groups that are related in some way and need to always exist on the same node, it is always best to have dependencies configured to ensure that when you fail over, both resource groups are always active on the same node. I came across this today, and opened up # smitty cm_rg_dependencies_menu and there were two ways to go about it: 1. Have a parent/child dependency, where one Resource group is a child of the other. 2. Configure an online on same node dependency. ... [More]
I had to create an AIX volume group and some filesystems on an AIX LPAR using NPIV connected to an HDS VSP Storage Array. The
first thing I did was install the ODM drivers, then HDLM, set the queue
depth on my LUNs and I was ready to create an AIX volume group.
# mkvg -S -f -y my_vg -s 256 -P 64 hdisk1 hdisk2
Changing the PVID in the ODM.
Changing the PVID in the ODM.
/usr/sbin/varyonvg: The varyonvg failed because the volume group's
This is mentioned in the NIM on AIX redbook.. http://www.redbooks.ibm.com/abstracts/sg247296.html If
you have NFS reserved ports enabled in AIX, then you need to make sure
these are set on the NIM master AND in your NIM client definition. If
you don't mksysb restores may hang on 0611 which is an issue with NFS. Progress Code 0611 - Explanation: Remote mount of the NFS file system failed. To turn on NFS reserved ports:
# nfso -po
# nfso -po nfs_use_reserved_ports=1
The fast path smitty nim_global_nfs can... [More]
There is a really good article here about how to create JFS2 snapshots in AIX: http://www.ibm.com/developerworks/aix/library/au-jfs2_snapshot.html This is a good way to get a point in time copy of an AIX filesystem, if your storage system doesn't have the capabilities of taking snapshots. The next problem is that of backing up the snapshots to TSM, and having your filespace naming correct. If you take a backup of /data by taking a snapshot of /data, and mounting it on /mnt/data that means that the TSM knows about /mnt/data which makes the... [More]
I had an instance where an AIX LPAR had it's rootvg LUN that it was booting from made unavailable.The obvious fix was to ensure that the rootvg LUN was available again, and re-start the LPAR. What I found interesting was that the LPAR was still responding to a ping, even with no operating system, and it was still up! Obviously I wasn't able to log in, the LPAR was pretty much dead so after re-starting it, all was ok. I was reading about the "rootvg event" in PowerHA 7.1. There is a good post about it here:... [More]
I have found reading blogs really useful on many occasions, to find out about new features, and more importantly how to get them working. In this case I’ll put one up about how to get SAN heartbeat working on PowerHA 7.1. The redbook PowerHA SystemMirror 7.1 for AIX sg247845 also has good information on this topic. One thing I setup recently was a two node PowerHA 7.1.1 cluster using SAN heartbeat. PowerHA 7.1 no longer supports a disk heartbeat, in it’s place SAN heartbeats can be used. The first thing that needs to be done is, to... [More]