Re: Expanding an LVM partition at the front
On Mon, 2011-02-21 at 21:00 +0100, Roberto Ragusa wrote: > On 02/21/2011 08:17 PM, Matthew Saltzman wrote: > > So is there a utility that can move the front of a physical volume > > partition? (gparted and fdisk apparently can't). > > [...] > Another probably much safer solution would be: > > - get a spare disk (even USB external one) > - create new PV, add to VG, pvmove your PV to the new PV > - destroy and recreate your PV > - pvmove from USB PV to enlarged PV > - remove USB PV > > This is less error prone. It can happen while the filesystem is R/W mounted > too. > That sounds like a better idea. (Probably slower though.) Thanks. -- Matthew Saltzman Clemson University Math Sciences mjs AT clemson DOT edu http://www.math.clemson.edu/~mjs -- users mailing list users@lists.fedoraproject.org To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines
Re: Expanding an LVM partition at the front
On 02/21/2011 09:17 PM, Richard Shaw wrote: > I'm not positive this would work and it certainly isn't elegant but... > > Could you just: > - Create a partition in the space preceding the current partition > - Add the partition to the existing vg > - Allocate those extents to the current lv > - Expand the file system to fill the now extended lv. > > I don't even like the idea, I'm just wondering if it would work. I > don't see why this would be any different that allocating extents from > several drives to make one lv / file system... It works perfectly. I'm doing it all the time. The original poster said he was evaluating this option too. -- Roberto Ragusamail at robertoragusa.it -- users mailing list users@lists.fedoraproject.org To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines
Re: Expanding an LVM partition at the front
On Mon, Feb 21, 2011 at 2:00 PM, Roberto Ragusa wrote: > On 02/21/2011 08:17 PM, Matthew Saltzman wrote: >> I deleted the partition immediately in front of an LVM physical volume. >> I'd like to use the freed space as part of the LVM volume group. I know >> I could create a new partition in the same place, make it a physical >> volume and add it to the group, but because the space is contiguous, I >> wondered if it is possible just to move the front of the existing PV >> partition to include the freed space. >> >> I tried changing the start of the partition using fdisk, but then the PV >> is no longer recognized by LVM. I suppose that means that there is >> information about the PV stored in a particular location at the front of >> the partition. Putting the starting point back makes the PV >> recognizable again. >> >> So is there a utility that can move the front of a physical volume >> partition? (gparted and fdisk apparently can't). > > What you are attempting is quite dangerous. > > I don't know if automated tools exist for this, but you should > do this: > > let's suppose you have this layout > > partition 5 cyl 1600-1999 empty space > partition 6 cyl 2000-2999 existing PV > > - destroy partition 5 and 6 with fdisk (not joking!) > - copy data from 2000-2999 to 1600-2599 (dd on /dev/sda with appropriate > bs,seek,skip,count) > - now create partition 5 on 1600-2599 > > At this point you should have your PV available again and you > have simplified your problem to "I want to enlarge a PV", which you can do > with fdisk (part5 from 1600 to 2999) and pvresize. > > Another probably much safer solution would be: > > - get a spare disk (even USB external one) > - create new PV, add to VG, pvmove your PV to the new PV > - destroy and recreate your PV > - pvmove from USB PV to enlarged PV > - remove USB PV > > This is less error prone. It can happen while the filesystem is R/W mounted > too. I'm not positive this would work and it certainly isn't elegant but... Could you just: - Create a partition in the space preceding the current partition - Add the partition to the existing vg - Allocate those extents to the current lv - Expand the file system to fill the now extended lv. I don't even like the idea, I'm just wondering if it would work. I don't see why this would be any different that allocating extents from several drives to make one lv / file system... Richard -- users mailing list users@lists.fedoraproject.org To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines
Re: Expanding an LVM partition at the front
On 02/21/2011 08:17 PM, Matthew Saltzman wrote: > I deleted the partition immediately in front of an LVM physical volume. > I'd like to use the freed space as part of the LVM volume group. I know > I could create a new partition in the same place, make it a physical > volume and add it to the group, but because the space is contiguous, I > wondered if it is possible just to move the front of the existing PV > partition to include the freed space. > > I tried changing the start of the partition using fdisk, but then the PV > is no longer recognized by LVM. I suppose that means that there is > information about the PV stored in a particular location at the front of > the partition. Putting the starting point back makes the PV > recognizable again. > > So is there a utility that can move the front of a physical volume > partition? (gparted and fdisk apparently can't). What you are attempting is quite dangerous. I don't know if automated tools exist for this, but you should do this: let's suppose you have this layout partition 5 cyl 1600-1999 empty space partition 6 cyl 2000-2999 existing PV - destroy partition 5 and 6 with fdisk (not joking!) - copy data from 2000-2999 to 1600-2599 (dd on /dev/sda with appropriate bs,seek,skip,count) - now create partition 5 on 1600-2599 At this point you should have your PV available again and you have simplified your problem to "I want to enlarge a PV", which you can do with fdisk (part5 from 1600 to 2999) and pvresize. Another probably much safer solution would be: - get a spare disk (even USB external one) - create new PV, add to VG, pvmove your PV to the new PV - destroy and recreate your PV - pvmove from USB PV to enlarged PV - remove USB PV This is less error prone. It can happen while the filesystem is R/W mounted too. -- Roberto Ragusamail at robertoragusa.it -- users mailing list users@lists.fedoraproject.org To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines
