Re: mdadm and whole disk array members

[Gary Dale <gary@extremeground.com>]

On 2021-03-22 18:49, Andy Smith wrote:
> Hi Gary,
>
> On Mon, Mar 22, 2021 at 06:20:56PM -0400, Gary Dale wrote:
> > I suggest that, since it appears the developers can't get this work
> > reliably, that the option to use the whole disk be removed and mdadm insist
> > on using partitions. At the very least, mdadm --create should issue a
> > warning that using a whole device instead of a partition may create
> > problems.
> I've been using whole disks in mdadm arrays for more than 15 years
> across many many servers on Debian stable and have never experienced
> what you describe. There must be something else at play here.
>
> I suggest you post a detailed description of your problem to the
> linux-raid mailing list and hopefully someone can help debug it.
>
>      https://raid.wiki.kernel.org/index.php/Linux_Raid#Mailing_list
>
> Cheers,
> Andy
It's not just me but a lot of other people have been having the same 
problem. It's been reported many times as I discovered after trying to 
use whole disks. Moreover, the fixes that I'd used in the past don't 
seem to work reliably without partitions.

There doesn't seem to be a downside to using partitions considering that 
partition tables have never taken up any significant amount of space. It 
was an interesting experiment / learning experience but I've decided 
that it's not worth going further so I'm going back to using disks with 
a single partition.