Comment 35 for bug 102973

On 12/14/2011 12:01 PM, bobdum wrote:
> So you intend that someone who want to migrate from a windows
> fakeraid to a "pure linux raid system" is obliged to have a second
> machine under *nux system, with the same (or higher) disk capacity,
> create mdadm and lvm volume support, and then can tranfer all
> datas... ?

If you are going to bother blowing away windows and rebuilding the
machine with Linux, then yes, I would expect you to backup your data,
rebuild the machine, and restore your data. You do have backups right?
  Raid is NOT a substitute for backups. You wouldn't want to keep your
data on an NTFS partition under a pure Linux install anyhow.

> Do you think is that the right way to solve this problem (and saying
> that fakeraid is buggy, i think you're a little bit shorty)... All
> the Intel chips(as concurrents) have well known handling protocols,
> and i think that the *buntu problem came from the idea to integrate
> all the managing of all the chips (promise, intell and so on) in an
> only one module.

I meant that it is fakeraid *support* in Linux that is buggy. Anything
beyond raid0 does not work well. mdadm also has additional capabilities
including being able to reshape the array to add/remove disks on the
fly, increasing ( or decreasing ) the capacity of the array, and true
raid10 ( not 0+1 ), so you can get both speed and redundancy with just
two or three disks.

> That is just a way of thinking (one patch for one chip can impact
> another).

It has nothing to do with chips; fakeraid is just software raid.

> Fakeraid is a hardware technology, and i think it is not possible to
> manage all chips in only one module. They have to be separated in
> two levels, hardware and software: hardware for the owner protocols,
> and a common part in the software for the user "gui" (or "ui" in
> console mode).

No, it isn't hardware technology; it is just plain old software raid
that bios vendors have built in support for, and a Windows driver that
reimplements the software raid differently from every other vendor, and
windows itself.

You can take fakeraid drives and plug them into a machine that does not
have any fakeraid support and Ubuntu will recognize and use them just
fine -- it doesn't care about the hardware.