On 23/08/2012, at 10.59, Miquel van Smoorenburg wrote: > On 23-08-12 10:34 AM, Bendtsen, Jon wrote: >> On 23/08/2012, at 09.58, Miquel van Smoorenburg wrote: >>> I've also filed this as a debian bugreport, >>> http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=684713 >>> >>> Linux md raid array devices come in two flavours: partionable >>> (/dev/md_d0) and non-partitionable (/dev/md0). Or at least, >>> that used to be the case, until kernel 2.6.28 where the two have >>> been consolidated. Now all md devices can have partitions. >>> >>> However, there is one minor oversight/bug in the kernel: the >>> sysfs "range" key is still set to "1" for md devices. That means >>> libparted thinks that it's not possible to partition that device, >>> when in fact it is. >> >> Which arguments are there for partitioning a software raid device? > > Well, first, because you can.. I have been running my personal server on a > partitioned md device (raid1) for a few years now. > > But the actual use-case here is Intel Matrix Raid ("imsm") support. Imsm is a > form of sataraid/fakeraid/biosraid that is supported by quite a few systems. > And this is supported by the Linux md driver (and "mdadm") as well. The md > device is then just the "system disk", and it has a partition table. > > The md driver has support for DDF formatted disks (industry standard portable > RAID layout) too. a DDF raid array will often have a partition table as well.
sounds reasonable, thank for taking your time to explain why it is a good thing.
