Re: [Libguestfs] [PATCH] New API: mdadm-stop for stopping MD devices.
On 23/11/11 16:22, Richard W.M. Jones wrote:
On Wed, Nov 23, 2011 at 03:02:19PM +0000, Matthew Booth wrote:
> On 23/11/11 14:43, Wanlong Gao wrote:
>> This API is used to stop a md device.
>> When we want to move a device to another md array, we should
>> stop the md device which contained this device first.
>
> I'm not convinced we should extend the md api in libguestfs to
> active manipulation. I wasn't convinced that mdadm-create was
> worthwhile either, but it made a test case ever so slightly tidier.
> To me, MD devices are the domain of physical machines. We need to be
> able to *read* them (for P2V apart from anything else), but I think
> manipulation is opening an unnecessary can of worms.
But is there any penalty to carrying this?
I can think of 2:
1. Maintenance: I know you think this is free, but some day mdadm --stop
might change behaviour, and then the api will break.
2. A false sense of expectation: Having an incomplete md api can only
lead to frustration. Implementing a complete md api would require a
large amount of effort for something which we don't have a convincing
use case for (i.e. nobody's ever going to use it anyway).
Matt
--
Matthew Booth, RHCA, RHCSS
Red Hat Engineering, Virtualisation Team
GPG ID: D33C3490
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