Replace SP2 CWS Host Documentation Request 1

[d3vzero]

Does anyone know of any documentation dealing with the whole system replacement of a CWS (Control Workstation) for a SP2 complex.

Now have a requirement for some SP2 nodes to go to Aix5.2, which inturn means that the CWS must also be taken to this level.

The problem is that our CWS Hardware architecture is RSPC, which is not supported by Aix5.2. (only CHRP architecture is supported at 5.2).

I have looked in the supplied PSSP documentation, and performed numerous net searches to no avail.

Now looking at bastardising the PSSP 3.2 Installation and Migration Guide to create the necessary procedures.

Currently CWS is at Aix4.3.3 with PSSP 3.2. The SP2 nodes are mixed at Aix4.3.3 with PSSP3.2, and Aix4.2.1 with PSSP2.4. (Note that there is no SP Switch involved).

If anyone has already performed this type of operation, or knows of documentation/links describing the process, I'd love to hear from you.

Thanks and Regards to All, Peter.

 

[AIXSPadmin]

You are correct that the CWS has to be at the level of OS and PSSP that the nodes will be at. Are you going to purchase new hardware for the CWS. If so, why not DR the CWS and then upgrade it to 5.2/3.4? This would be the easiest approach.

 

[d3vzero]

Thanks for the response.

We already have an existing F50 (CHPT) box that I'm thinking of using to replace the current CWS.

Your suggestion is exactly what I've been planning (ie the replacement of the CWS system) ... but I cant find any specific docs on the procedure to achieve it.

Are you awear of any ???

 

[AIXSPadmin]

Go to the IBM Redbooks website and then look for the "RS/6000 SP System Management: Power Recipes for PSSP 3.1"

You may not be at this level of PSSP, however, in chapter 2 there is a section on backing up/restoring the CWS. I am not sure what volume groups you have, but normally it is just rootvg and spdatavg. I have DR'd a couple of CWS's before and everything went smooth and there was a complete recovery.

 

[d3vzero]

Thanks for the documentation info.

It caters to situations where you are restoring a mksysb image of rootvg, and a savevg image of spdata.

Our own situation involves the breaking of a HACWS pair, which means that the mksysb of the rootvg is useless to me. I can however use the spdata_vg.

The "Power Recipes" docs led me to re-examine the "PSSP 3.2 Installation and Migration Guide" which covers Migrating to the Target AIX Level via BOS Overwrite/Preservation Install in Chapter 4. (Hopefully just the ticket).

I will add the results to this thread on completion.

Thanks again for your help.

Best Regards, Peter.

 

[AIXSPadmin]

Good luck on your implementation. I have heard that using HACWS is not worth the headaches and hassles and it is easier to just have a standalone CWS that can be restored.

 

[d3vzero]

Could not agree more.

There may be some site somewhere where the price/risk of loosing its Control Workstation for a few hours is truly un-acceptable (and so worth the extra cost/maintenance/admin overheads) ..... but this one aint it ;-)

 

[franksoprano]

Why dont you keep your current CWS alive until you get the new box that you will soon use as the new CWS and create a HACWS so to speak, meaning you will be using the new box as a backup CWS until you have it completely configured and patched and running the latest PSSP level along with any required patches.

Couldnt you build the new CWS with 5.2 and load the highest level of PSSP onto it, and then restore the SDR from your current CWS to the new CWS? Or how about rebuilding the current CWS onto the new box and migrating/upgrading all the software levels that you need?

Just a few ideas that I had in mind. Before you begin the great journey to constructing a new CWS make sure you have some good backups of your current CWS.

Good Luck!


Frank-

 

[d3vzero]

Thanks for the ideas Frank.

I had thought of building the new CWS box at 5.2, and then cutting over the SDR .... but the SDR would not be compatable at the new software levels.

I had also thought to integrate the new CWS box into the HACWS cluster .... but this is a one way operation.

Once a CWS is configured into a HACWS the only way to drop the HA config is to either restore a mksysb image of the box pre its config to HACWS .... or to totally reinstall the OS.

Seeing as we only have one replacement box of the correct architecture to support Aix 5.2, the continued use of HACWS is no longer an option. (and its not really required here anyway).

The only way of doing it cleanly that I can see is to build the replacement at exactly the same software levels. Then cut it over to support the SP2 complex, leaving the old CWS as a disconnected backup. Once this is stable we will then perform a migration install of the Aix and PSSP software on the new CWS.

And for the duration of this process "backups" will be my middle name ;-)

Thanks for the thoughts.

Regards, Peter.

 

[franksoprano]

Peter,

That was running through my head, wondering if the backup of your SDR would be compatible withe the latest and greatest level os PSSP.. Are you sure about that?

Let me know how you make out once everything is up and running as it should be...

Take Care!

Frank-