From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Heinz J . Mauelshagen" Subject: Re: [linux-lvm] Just for information .... Message-ID: <20011123130149.A4829@sistina.com> References: <3BFAA389.24AAB2A1@LTUtech.com> <20011120125632.Z1308@lynx.no> <20011120214104.A24005@cistron.nl> <20011120150638.E1308@lynx.no> Mime-Version: 1.0 In-Reply-To: <20011120150638.E1308@lynx.no>; from adilger@turbolabs.com on Tue, Nov 20, 2001 at 03:06:38PM -0700 Sender: linux-lvm-admin@sistina.com Errors-To: linux-lvm-admin@sistina.com Reply-To: linux-lvm@sistina.com List-Help: List-Post: List-Subscribe: , List-Unsubscribe: , List-Archive: Date: Fri Nov 23 06:07:02 2001 List-Id: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-lvm@sistina.com On Tue, Nov 20, 2001 at 03:06:38PM -0700, Andreas Dilger wrote: > On Nov 20, 2001 21:41 +0100, Wichert Akkerman wrote: > > Previously Andreas Dilger wrote: > > > Yes. You will need to do a vgscan to find the new disks. Hopefully they > > > will not have the same VG name as another VG on that system. > > > > What if they do? > > Then it will depend on disk ordering which one you get under that name, and > the other will be unavailable. vgscan will see all of the disks, but then > start checking the UUIDs on the PVs against the list on the "first" disk, > and the extra disks with UUIDs that don't match will be discarded. Worst case would be a temporary disconnect of the PVs belonging to one of the VGs which share the same name. vgscan+vgrename the found one and reconnect the drives and vgscan again. > > I don't think there are any likely scenarios with LVM 0.9+ that will cause > problems, but since UUIDs were only introduced in 0.9, it may be much harder > to handle this in older LVM versions. See above. > > You might be able to vgexport the disks from the "other" VG at that time, > and reimport it with a different name, but I don't know how reliable that > will be (if it even works). LVM has been confused by less. ??? > Better to just > "not do that" in the first place. > > FYI, AIX LVM does not keep the VG name on the disk itself, only a UUID. > You also never do something like "vgscan" at boot time to reconfigure > the LVM setup. When you attach the disks to a new system, you have to > import them (at which point they get a name that is stored in a config > file in /etc), and your LVM config is never touched until you change it. > When you export the VG, it also doesn't write to the disks, just deletes > the config from /etc. This means you don't need to do anything to the > VG before moving it to another system. Well, actually you can just "vgscan" in the VG without vgexport'ing it in Linux LVM as well. vgexport/vgimport exactly is the clean procedure to make sure that name clashes don't happen! > > Cheers, Andreas > -- > Andreas Dilger > http://sourceforge.net/projects/ext2resize/ > http://www-mddsp.enel.ucalgary.ca/People/adilger/ > > > _______________________________________________ > linux-lvm mailing list > linux-lvm@sistina.com > http://lists.sistina.com/mailman/listinfo/linux-lvm > read the LVM HOW-TO at http://www.sistina.com/lvm/Pages/howto.html -- Regards, Heinz -- The LVM Guy -- *** Software bugs are stupid. Nevertheless it needs not so stupid people to solve them *** =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- Heinz Mauelshagen Sistina Software Inc. Senior Consultant/Developer Am Sonnenhang 11 56242 Marienrachdorf Germany Mauelshagen@Sistina.com +49 2626 141200 FAX 924446 =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-