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<TITLE>RES: RES: [DRBD-user] software RAID, LVM</TITLE>
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<P><FONT SIZE=2>>Thank you, Leonardo, this is very helpful! I have a better understanding >now,<BR>
>but one more question:<BR>
<BR>
>On Thursday 02 February 2006 11:00, Leonardo Rodrigues de Mello wrote:<BR>
> Hi Nate,<BR>
> -----Mensagem original-----<BR>
><BR>
> >De: drbd-user-bounces@lists.linbit.com em nome de Nate Reed<BR>
> >Enviada: qui 2/2/2006 14:41<BR>
> >Para: General Linux-HA mailing list<BR>
> >Cc: drbd-user@lists.linbit.com<BR>
> >Assunto: [DRBD-user] software RAID, LVM<BR>
> ><BR>
> >Here's what I was thinking of doing on each machine:<BR>
> ><BR>
> >disk 1<BR>
> > - swap partition<BR>
> > - / partition<BR>
> > - Linux RAID partition<BR>
> ><BR>
> >disk 2<BR>
> > - Linux RAID partition<BR>
><BR>
>I wonder if I could refine this scheme to add redundancy of / and swap as<BR>
>follows:<BR>
><BR>
>disk 1<BR>
> - RAID 1 (md0)<BR>
> - RAID 2 (md1)<BR>
>disk 2<BR>
> - RAID 1 (md0)<BR>
> - RAID 2 (md1)<BR>
><BR>
>Create two RAID devices, for example: /dev/md0 (for disk1/RAID1 and disk<BR>
>2/RAID 1) and /dev/md1 (for disk 1/RAID 2, and disk 2/RAID2). <BR>
<BR>
You can do this, but if you want to use a linux software raid as ROOT (/), you must use raid-1, or create one single partition for /boot. this is a limitation of grub/lilo to access the kernel and initrd images.<BR>
<BR>
<BR>
><BR>
>DRBD would access /dev/md0, and there are LV's / and swap on /dev/md1. This<BR>
>should insulate LVM against failure of one of the disks.<BR>
<BR>
Does you realy need to use LVM ? i have bad experiences with it, like having some problem with my lvm volumes, sending 300 GB of files in lost+found. i never had problems with software raid. :-D<BR>
<BR>
><BR>
>What do you think of this?<BR>
><BR>
>Nate<BR>
<BR>
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