Re: clustered MD

David Lang
2015-06-09T20:33:21Z

On Tue, 9 Jun 2015, David Teigland wrote:

>> We do have a valid real world utility. It is to provide
>> high-availability of RAID1 storage over the cluster. The
>> distributed locking is required only during cases of error and
>> superblock updates and is not required during normal operations,
>> which makes it fast enough for usual case scenarios.
>
> That's the theory, how much evidence do you have of that in practice?
>
>> What are the doubts you have about it?
>
> Before I begin reviewing the implementation, I'd like to better understand
> what it is about the existing raid1 that doesn't work correctly for what
> you'd like to do with it, i.e. I don't know what the problem is.

As I understand things, the problem is ~providing RAID across multiple machines,
not just across the disks in one machine.

David Lang