Boot AIX from SAN

There is an excellent document available on PowerLink:

"EMC Host Connectivity Guide for IBM AIX"

This includes much of the information you will need for just about any connectivity questions for AIX.

Checking the connectivity guide is the way to go. The nice thing with most UNIX variants is that you can control the bootlist from the OS level via utilities without having to muck with HBA BIOS screens.

For example in regular AIX (this changes a little bit if you are doing LPARs or other virtualization) you can use the bootlist command to view and alter your boot path.

Now if you are talking Linux you are back into the BIOS screens...

Yes, the connectivity guide is definitely helping me in getting off the ground.

After reading some of the document, I started to think about the fact that no where in the doc does it mention enabling the BIOS?

If you look at the tasks as a laundry list it goes as follows for New Install:

Install HBA into AIX Server with locally install OS
Update system/service processor microcode
Update HBA microcode
Zone/Mask future boot LUN to HBA in server
Assign PVID to disk
Pull internal disk
Load AIX CD and designate SAN disk as boot device
Load EMC ODM

So no where do you actually enable the BIOS on the HBA?
Being a Windows Admin, I find this strange since the Intel Hardware will not even see the disk unless the BIOS is enabled but the RS/6000 AIX will?


I am also unclear...once you get a single HBA enabled, you would then want to load powerpath and then install a second HBA. Once you do that will everything still work properly?

Again, I am not an AIX admin but I do want to learn..
Any help would be appreciated
Chris

Easiest way to think about this is IBM owns the hardware and OS so the integration between the hardware boot and the OS boot process is tighter. There is certainly a much deeper technical reply to it, but that is the easiest way to think about it.

Obviously the boot loader for the OS has to be able to talk via the adapter that gets to the disk, but IBM integrates that in natively in the bootloader they completely control. There are some advantages to having the same vendor control the whole server package

As for the multiple path question, AIX (and most major UNIX variants) have native support to handle multiple paths to a device so you do not need to worry about having one path unplugged while you load PowerPath. With UNIX you'll enjoy the advantages of a real volume manager which provides quite a bit of flexibility (so much that you can hang yourself) with how you use your storage. In fairness I think Windows 2008 will finally move Windows into the realm of native multipath. Why do you use PowerPath in UNIX? Really mostly to get over the fact that the default is usually just active/passive failover mode where PowerPath gives you the ability to do more intelligent load balancing.

Hope this helps. AIX is definitely the easiest UNIX to pickup coming from Windows as IBM has put a lot of tools around it. It is like UNIX with training wheels ... let the flaming begin

If you ask for flames, you'll get flames

You should know that AIX is an acronym .. AIX = Aix Isn't uniX ...

Please tell me any other unix that have a "tcpmgr" command .. I've been told that AIX 5.2 (and later) are a lot better (I'd say a lot unixer) but I still remember what I had to do when I wanted to change the IP address of an AIX host .. I still have nightmares !!


Message was edited by:
Stefano Del Corno

I appreciate your insight...

This week I will be testing boot from SAN with AIX

We shall see how it goes.

Thanks again for all the input
Chris