Edit: Some links no longer work.
Originally posted August 24, 2010 on AIXchange
I love getting tips and tricks, and hopefully you love it when I share them. For instance, recently while perusing a mailing list, I learned of a simpler way to look up IBM employee contact information from a smartphone. At least for me, this just seems to render better on my phone than the more familiar URL (whois.ibm.com) that many of us have bookmarked on our browsers.
Thanks to the same mailing list, I was reminded of something else: You can still create a physical hot spare disk in a volume group. This capability has been available through the AIX logical volume manager since AIX 5.1, but of course, with the advent of SANs and shared storage, we’re far less reliant on internal and direct-attached disks these days. But even though we don’t need hot spares the way we once did, it’s good to know that this option remains available.
In the days of SSA drawers I used hot spares all the time. Knowing the hot spare would immediately take over when a disk failed was, to put it mildly, reassuring. Then I’d just place a quick service call, and the CE would come replace my old disk or IBM would ship me a disk and I’d replace it myself.
Here is a detailed definition of hot spares.
I’ll also highlight these steps for enabling hot spare support. Although this document uses websm rather than smit, the concepts are still the same. To select your volume group, go to smit lvm > Volume Groups > Set Characteristics of a Volume Group > Change a Volume Group. Then in the smit panel, change Set Hotspare Characteristics to y.
“Beginning with AIX 5.1, you can designate hot spare disks for a volume group to ensure the availability of your system if a disk or disks start to fail. Hot spare disk concepts and policies are described in AIX 5L Version 5.2 System Management Concepts: Operating System and Devices. The following procedures to enable hot spare disk support depend on whether you are designating hot spare disks to use with an existing volume group or enabling support while creating a new volume group.
Enable Hot Spare Disk Support for an Existing Volume Group
The following steps use Web-based System Manager to enable hot spare disk support for an existing volume.
1. Start Web-based System Manager (if not already running) by typing wsm on the command line.
2. Select the Volumes container.
3. Select the Volume Groups container.
4. Select the name of your target volume group, and choose Properties from the Selected menu.
5. Select the Hot Spare Disk Support tab and check beside Enable hot spare disk support.
6. Select the Physical Volumes tab to add available physical volumes to the Volume Group as hot spare disks.
“At this point, your mirrored volume group has one or more disks designated as spares. If your system detects a failing disk, depending on the options you selected, the data on the failing disk can be migrated to a spare disk without interruption to use or availability.
Enable Hot Spare Disk Support while Creating a New Volume Group
The following steps use Web-based System Manager to enable hot spare disk support while you are creating a new volume group.
1. Start Web-based System Manager (if not already running) by typing wsm on the command line.
2. Select the Volumes container.
3. Select the Volume Groups container.
4. From the Volumes menu, select New > Volume Group (Advanced Method). The subsequent panels let you choose physical volumes and their sizes, enable hot spare disk support, select unused physical volumes to assign as hot spares, then set the migration characteristics for your hot spare disk or your hot spare disk pool.
“At this point, your system recognizes a new mirrored volume group with one or more disks designated as spares. If your system detects a failing disk, depending on the options you selected, the data on the failing disk can be migrated to a spare disk without interruption to use or availability.”
Here’s an update to last week’s blog post about the new POWER7 servers:Here are the supported operating systems: AIX 7.1, AIX 6.1TL6, AIX v5.3 TL12 SP1 or later, IBM i 7.1, IBM i 6.1 with 6.1.1 MC or later, VIOS 2.2 or later and HMC V7R720 or later.
While this will be true at GA, on 9/30 we should see support for AIX V5.3 TL10 SP 5, or later and AIX V5.3 TL11 SP 5, or later.