topic Re: split root vg in Operating System - HP-UX

split root vg

Lisa Moore — Thu, 17 May 2001 11:56:52 GMT

The root vg that I am trying to mirror is split on 2 disks. There is room on either to have everything on one, but how do I get it there?

Re: split root vg

Vincenzo Restuccia — Thu, 17 May 2001 15:16:36 GMT

See man lvsplit and lvmerge.

Re: split root vg

David Hixson — Thu, 17 May 2001 15:18:07 GMT

Lisa,

You should pick whichever drive has / (root), /stand, and your primary swap on it. Then use the pvmove command to re-locate the lvols off of the other disk onto the one you have chosen.

For the sake of having to administer it in the future, try to make sure each lvol has contiguous physical extents, and that when you mirror them, that they mirror up in the same order.

This is a BAD time to use SAM.

Re: split root vg

Vincenzo Restuccia — Thu, 17 May 2001 15:21:56 GMT

Hi, again see http://docs.hp.com/cgi-bin/fsearch/framedisplay?top=/hpux/onlinedocs/B2355-90672/B2355-90672_top.html&con=/hpux/onlinedocs/B2355-90672/00/00/72-con.html&toc=/hpux/onlinedocs/B2355-90672/00/00/72-toc.html&searchterms=lvsplit&queryid=20010517-092030

Re: split root vg

James R. Ferguson — Thu, 17 May 2001 15:22:07 GMT

Hi Lisa:

It would be helpful if you would describe which logical volumes are where. In the absence of this information, I'll offer several comments for consideration:

> One way to consolidate everything on one physical disk and afterwards mirror to a second is to make an Ignite 'make_tape_recovery' tape and cold-install your vg00. You would also have the advantage of being able to resize each logical volume according to your needs at that time.

> Depending on where logical volumes exist, it might be possible to 'pvmove' some of the extents form one disk to the other. Before doing this, however, I would make a good 'make_tape_recovery' tape too.

...JRF...

Re: split root vg

Lisa Moore — Thu, 17 May 2001 15:50:15 GMT

Thanks once again for all of your help.

After doing an lvdisplay -v /dev/vg00, the only mountpoint of concern would be lvol4, which was swap with 0% utilization. It isn't needed and we were thinking that just removing it and then mirroring would be the answer, but are not sure of whether or not it would cause any problems.