The XIV Host Attachment Kit

As you would expect, the IBM XIV supports a very wide range of Host Operating Systems. Even better, for most of these Operating Systems, IBM makes available (free-of-charge) a multipathing kit to install on these hosts.  We call this the Host Attachment Kit, or HAK.   You can find all of the available Host Attachment Kits at the IBM Support site found here. You will find HAKs for AIX, HP-UX, Linux, Solaris and Microsoft Windows.

What is important is that if the HAK is available for your Operating System,  we need you to always install it on every host that attaches to IBM XIV.   We ask this for the following reasons:

  1. By having the XIV HAK installed, your hosts are much easier for IBM to support. This is because installing the HAK ensures that your multipathing is setup correctly.  When you installing the HAK and then run the xiv_attach command, the HAK will adjust system parameters to optimal values. For example on Windows hosts it ensures that the required MPIO Service is running and that the recommended hot fixes are installed.  For Linux hosts it ensures that the multipath.conf file is correct.  Every time you map a new volume from your IBM XIV, use should run xiv_attach to ensure you continue to have the correct settings.
  2. If you have an issue that requires IBM support, the HAK supplies a command known as xiv_diag.  This command creates a zipped host log file that will contain useful and relevant information for IBM to analyze.
  3. The HAK supplies a very valuable command known as xiv_devlist which lets you list all attached volumes and match the host ID to the XIV volume name.   If your host is attached to multiple XIVs, you can also map each volume back to it’s relevant XIV.  Its a command I cannot live without…  I love it!

Here is an example of what xiv_devlist will tell you.  In this example I have run it on a Windows 2008 machine, but the output is basically the same regardless of host operating system.  You can see the operating system identifier (the Device as reported by the operating system, in my example PHYSICALDRIVE0), the name of the volume (as seen on the XIV, in my example W2K8X64-H02_BOOT – Exchange) and  the serial number of the XIV providing the volume (in my example 6000081)

The operating system device identifier lets you map an XIV volume from XIV to host. So in this example, I know that the Windows (C:) drive, which is Windows Disk 0, maps to a volume on the XIV known as W2K8X64-H02_BOOT – Exchange.

And to finish, there are several other commands that are very helpful.  For instance the xiv_fc_admin -P command will tell you your WWPNs.

C:\Windows\system32> xiv_fc_admin -P
21:00:00:0d:60:13:b0:8c: [QLogic IBM FCEC Fibre Channel Adapter]: IBM FCEC
21:00:00:0d:60:13:b0:8d: [QLogic IBM FCEC Fibre Channel Adapter]: IBM FCEC

Another useful command is xiv_fc_admin -R because it rescans your bus.  In some operating systems it is not obvious how to do this (other than reboot of course).

The nice thing is that regardless of your host operating system, the commands are the same.  This is possible because they use the Python programming language.  You may notice Python being installed as xpyv when you install the HAK (it is so named to ensure it doesn’t interfere with any other Python installs you have).

So please install the HAK on every host that attaches to XIV.   You will be making everyones life a lot easier (especially your own).

Oh and by the way, you can confirm whether your Host Operating System can be attached to the XIV by consulting the IBM System Storage Interoperation Center (or SSIC).   If the HAK is not available for your Operating System, the SSIC will list other Vendor approved multipathing solutions (such as Veritas DMP).


About Anthony Vandewerdt

I am an IT Professional who lives and works in Melbourne Australia. This blog is totally my own work. It does not represent the views of any corporation. Constructive and useful comments are very very welcome.
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7 Responses to The XIV Host Attachment Kit

  1. Troels Arvin says:

    On Linux, the HAK seems to have a very annoying habit of setting user_friendly_names to “yes”; this can really wreck havock if you run xiv_attach on a server which already has a working multipath-setup with user_friendly_names set to “no” (the only sane value, in my opinion). So I think that the HAK is too intrusive.

    • avandewerdt says:

      Hi Troels.

      This is is interesting as I have migrated quite a few Linux hosts to XIV, either from having no MPIO or having EMC Power Path, so far without complaint about name changes.

      Can you send me an email detailing how things got changed and what affect it has?
      I am happy to write a blog post about it and/or take it up the line.
      My email address is:

  2. Mike B. says:

    Is there a HAK for VIO?

    • avandewerdt says:

      You install the AIX host attachment kit.
      The AIX kit version 1.6 is supported to be installed on:
      1. AIX 5.3 ‐ TL07‐12
      2. AIX 6.1 – TL00‐05
      3. VIOS 2.1.1 to 2.1.3

  3. Bear says:

    Anthony, When upgrading HAK, is thre a required/preferred method.
    Example: Does VIO need to upgrade prior to any of the LPARs?
    Is HAK upgrade example 1.5 to 1.8 concurent or does it require stopping I/O to XIV.
    What if OS is boot from XIV, can that be concurrent upgrade?

    • Great questions.
      You can do the HAK upgrade online for the most part as it just upgrades scripts.
      The only exception would be if the HAK also installs patches (which the Windows one usually does).
      The way to tell what affect the HAK would have is to do a dry-run with the portable version.
      This will tell you if an outage is needed.

      The command is: xiv_fc_admin -V
      I documented this here:

      As for VIO vs LPAR, I would definitely do the VIO first, LPARs second.

  4. Rob says:

    I hope this blog is still live! I have to upgrade the HAK on our VIO servers. If I upgrade VIO1 HAK, will the connections be rolled to the VIO2 server or will VIO1 continue without problems? You mentioned the scripts are upgraded…so that in theory should not affect the performance..
    Linux and aix HAK upgrades have not req’d restarts, that I can remember.
    What is your experience?

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