Single VPAR Modification

[Tim Hempstead]

We currently have a development npar on our Superdome which is configured as a single vpar, (so as to match production in configuration which runs multiple vpars in an npar). We are adding hardware to the development npar so that the existing vpar can be expanded and a second one created. The hardware needs to be added to the existing vpar urgently, (its having major issues due to lack of memory), and we need to expand it before we can create the second vpar.

Now my problem is how to expand the vpar. On our production environment I would stop the vpar to be changed and then run a vpmodify command from another vpar to change the stopped one ... but here i do not have a second vpar to work from.

Would it be best to do the following:

1). modify the configuration to an alternate vpar database and reboot using that.

2). boot the vpar as an npar and then change the configuration, (hmmm .... would i be able to run a vpmodify here or would i have to remove the vpardb and run vpcreate to redefine the vpar from scratch, (not an issue as I have the original definition documented)).

I would be adding 2CPU (bound) and 8GB of memory to the vpar (currently it has 4CPU (bound) and 16GB of memory).

The outage required to do this is not to much of an issue as the users _really_ want the existing system expanded.

Many Thanks

Tim

[D Block 2]

Tim,

You might just add the new h/w, lan, memory, etc. to the npar where the development vpar resides. then issue the vparstatus -A command. Once you see the new available h/w, then figure you can create a New vpar by running the vparcreate command.

btw, regarding memory for vpar's.. I would also consult w/ your CE, somehow I think the memory added has to be layed out evenly-dimms.. (this might not be an issue, but adding memory for vpar, you just might want to ask your CE.)

also, if you do boot your vpar as a hard-par, not a problem, but I'm not certain if you can edit the vpdb.. I think the database if binary..file. and can't be edited.

[Tim Hempstead]

Tom,

You misunderstand my question.

Yes I know I can create a new vPar by adding hardware to the nPar and then just executing the vpcreate command, that it is not my problem. Adding memory to an nPar, the memory should be balanced between the cell boards, here both boards will have 16GB.

The problem is with changing the the configuration of the existing vPar. Yes I know I cannot edit the vpardb when booted as a nPar as its a binary file, I'm not asking whether I can do that. I am asking how I can change the vPar configuration in that state, i.e. can I use vpmodify, (but does this need to hav vpmon running to work, i.e. be executed from another running vPar in the same nPar) or do i need to remove the vpardb and recreate the vPar configuration using vpcreate ?

Tim

[melvyn burnard · Accepted solution]

to modfity the single vPar, you will need to reboot the "system" back as an nPar, and then make the changes. I think vparmodify should work, but if not then you will need to vprremove the vpar, then recreate it.
I believe vparmodify should work without the vpar running

[D Block 2]

guys, I'm not the expert here, but.. if you boot the npar (not running from vpmon), then its just an npar.. any vPar commands like vparmodify need to sync with the vpmon's database.. I'm a little concerned here that one can boot as an nPar, but then run vparmodify to update the vpar db. that's cool if it works.

Tim, you might want to boot as an npar, and then do a full Ignite make-recovery, before trying options out.

keep us posted, I'm interested in your progress.

[Tim Hempstead]

Thanks Guys.

I think I've found the some info buried in the depths of the vpmodify man page ... it seems to say that you can use vpmodify when not running as a vpar, i.e. no vpmon process running, but you must specify the vpar database file using the -D option ... the man page says, (I'm going from the hard copy in Appendix A of the Poniatowski vPar book, middle of pg 958), "If the -D option is omitted, the virtual partition monitor must be running." This seems to imply that the opposite would be true.

I'll up date the thread with results when I have them.

[Tim Hempstead]

Ok, The work is now complete. Using the -D switch on the vparmodify dfid work as expected and did allow us to modify the vPar configuration whilst in vPar mode. The only issue we had was that the core i/o associated with one of the new cell boards took over as master core i/o for one of the nPars hence we only had read only console access until we added that io path to the vPar config.

Regards

Tim