[Mageia-dev] time to switch from raw partitions to lvm?

Mon Feb 21 21:38:07 CET 2011

On Monday, 21 February 2011 18:56:22 Jeff Robins wrote:
+> > Michael Scherer wrote:
+> > > For a linux system, a lvm logical volume is just another disk.
+> 
+> I've had issues in the past because Linux considered LVM just one logical
+> disk and I think the average user would eventually have the same problem as
+> well.  I think moving to LVM as the default will create too many complaints
+> and support requests in the end.
+> 
+> A long time ago I had a system with 6 SCSI disks, each 1.2GB.  The system
+> was fairly useless with the single disks, but using LVM I had 1 disk of
+> reasonable size.  I ran the system for about a year with no problems, but
+> then 1 of the disks failed.  Normally this would be a medium inconvenience,
+> because I would just have to restore the files from that one drive to
+> another drive. However, with the LVM,
+
+... or RAID0 ...
+
+> I lost the ability to read the entire
+> LVM.
+
+VG.
+
+> I had to restore the entire system, which was a much bigger pain.  I
+> also could not obtain a disk of the same small size for a reasonable price,
+> which I was told would make the problem even bigger.
+
+Irrelevant for LVM. Only partly relevant for RAID0.
+
+> If I had used some redundancy, then I might have been able to restore the
+> one disk, but I was a novice user and didn't understand the need.  I think
+> that most users who use the defaults and probably novice users, or at least
+> will be after Mageia takes off.  I think LVM support is a must, but I think
+> making it the default, without also making some redundancy the default,
+> will cause more problems than it solves.
+
+For single-disk systems, there is no difference.
+
+For multi-disk systems, whether it would have been any different depends on 
+whether you had a single VG or multiple VGs.
+
+But, by the time you talk about 6 disks, we're not talking about a default 
+anymore.
+
+Regards,
+Buchan
+