Configuring the AIX operating system

You must configure the AIX® operating system to use IBM® Power Systems hosts with the system.

Configuring for fast fail and dynamic tracking

You must enable the fast fail and dynamic tracking attributes for hosts systems that run an AIX 5.2 or later operating system.

Before configuring your host system to use these attributes, ensure that the host is running the AIX operating system version 5.2 or later.

To configure your host system to use the fast fail and dynamic tracking attributes follow these steps.
Note: These steps need to be taken only on systems running AIX 6.1 or 5.2. The commands require the fscsiX device to be in the defined state.
  1. Issue the chdev -l fscsi0 -a fc_err_recov=fast_fail command to set the Fibre Channel SCSI I/O Controller Protocol Device event error recovery policy to fast_fail for each Fibre Channel adapter. This example command is for adapter fscsi0.
    Note: By default, dynamic tracking is enabled on all systems running AIX 7.1.
  2. Issue the chdev -l fscsi0 -a dyntrk=yes command to enable dynamic tracking for each Fibre Channel device. This example command is for adapter fscsi0.

Multipath support for IBM Power Systems hosts

You must install multipathing software on all IBM Power Systems AIX hosts that are attached to the system.

On IBM Power Systems hosts, the AIX Path Control Module (AIXPCM) provides multipathing support.

For more information about the multipath drivers, see www.ibm.com/support.

Configuring system devices with multiple paths per LUN
  • The system supports multiple LUNs on an IBM Power Systems AIX host.
  • The system supports multiple path configurations for a LUN. You can have multiple hdisks (logical hard disks) available on the host for each physical LUN.
  • To configure multiple paths for all LUNs, run the cfgmgr command to scan for new devices.
    • If you are using the AIX Path Control Module (AIXPCM) and want to check whether the multipath device is available, run the lsdev command and search for the hdisk# line with the MPIO IBM #### FC Disk label against it.

For more information about which multipath driver to use, see http://www.ibm.com/support.

SAN boot support for IBM Power Systems hosts

You can reload the operating system from a boot disk on the SAN over Fibre Channel. You can initiate this process from the system volume if your IBM Power Systems hosts use AIX operating system version 5.3 or later.

You must use the AIX Path Control Module (AIXPCM) to boot from the SAN. Create an installation volume and map it to the host. Proceed with the installation per the AIX installation instructions and, when you are prompted, select the previously defined volume as the target installation disk.

Dynamically increasing volume size

If your IBM Power Systems AIX hosts use AIX 5.2 or a later AIX operating system version, the system supports the ability to dynamically increase volume size.

The chvg command options make it possible to increase the size of a physical volume that the Logical Volume Manager (LVM) uses, without interruptions to the use or availability of the system. See the AIX publication System Management Guide: Operating System and Devices for more information.

Virtual input/output for IBM Power Systems hosts

The system provides both single and dual Virtual input/output (VIO) server configurations on IBM Power Systems hosts that support VIO.

You can present the system volumes to the VIO server host bus adapters (HBAs) by using the same method as a standard AIX installation. For single VIO server configurations, volumes can be split up into logical volumes by the VIO server and mapped to the VIO clients. For dual VIO server configurations, volumes cannot be split into logical volumes, and must instead be mapped intact through both servers to the VIO clients.