On Mon, Sep 2, 2013 at 12:36 PM, Nick Holland <n...@holland-consulting.net>wrote:
> On 09/02/13 08:19, John Hynes wrote: > ... > > The "new" sd2 is identical to the old, which is identical to the other > > disks. > > you provide ZERO proof of this, which makes me guess that you buy disks > of the same maker and same model number and assume the rest. > > This is very often wrong. > > Proof of that is hanging out of my hw raid box on this computer right > now -- two "identical" drives, purchased on the same date from the same > store. one is a few sectors larger than the other. Smaller drive can > be mirrored to larger, larger can not be mirrored to smaller. > > Nick. > > I posted a dmesg earlier in the thread, that showed all three drives had the same number of sectors as far as the kernel is concerned. After replacing the drive with the one I "assumed" to be identical (a new sd2), here's what the kernel thought: sd2: 476940MB, 512 bytes/sector, 976773168 sectors For reference, here's what I posted in the other message from dmesg: sd0: 476940MB, 512 bytes/sector, 976773168 sectors sd1: 476940MB, 512 bytes/sector, 976773168 sectors