Re: [parted-devel] [PATCH 1/2] Add nonfs partition type 0xda (#1263835)

Re: [parted-devel] [PATCH 1/2] Add nonfs partition type 0xda (#1263835)

[Phil Susi]

On 10/8/2015 5:49 PM, Brian C. Lane wrote:
> https://bugzilla.redhat.com/show_bug.cgi?id=1118065 has a pile of
> discussion on it.
> 
> What it amounts to is that on msdos partitioned disks mdadm only wants
> 0xfd to be used for version 0.90 arrays which the kernel can
> autoassemble, for 1.x arrays some other type needs to be used.

So use 0x80?  That's what I always have done and it has never been a
problem.  Likewise, 0xfd won't cause a problem either: it will trigger
kernel auto activation *if* you boot with no initramfs, *and* the
partition does contain 0.90 metadata.  If it has 1.x, then it won't
trigger auto activation, but has no other negative consequence.

I see from the discussion in that bug report that the mdadm man page
recommends this type code.  Is there any reason for that recommendation?
 Are there any consequences to not following it?  Cc'ing mdadm list to
see if they can answer this.

Re: [PATCH 1/2] Add nonfs partition type 0xda (#1263835)

[Brian C. Lane]

On Fri, Oct 09, 2015 at 11:02:25AM -0400, Phil Susi wrote:
> On 10/8/2015 5:49 PM, Brian C. Lane wrote:
> > https://bugzilla.redhat.com/show_bug.cgi?id=1118065 has a pile of
> > discussion on it.
> > 
> > What it amounts to is that on msdos partitioned disks mdadm only wants
> > 0xfd to be used for version 0.90 arrays which the kernel can
> > autoassemble, for 1.x arrays some other type needs to be used.
> 
> So use 0x80?  That's what I always have done and it has never been a
> problem.  Likewise, 0xfd won't cause a problem either: it will trigger
> kernel auto activation *if* you boot with no initramfs, *and* the
> partition does contain 0.90 metadata.  If it has 1.x, then it won't
> trigger auto activation, but has no other negative consequence.
> 
> I see from the discussion in that bug report that the mdadm man page
> recommends this type code.  Is there any reason for that recommendation?
>  Are there any consequences to not following it?  Cc'ing mdadm list to
> see if they can answer this.
> 

I think their thinking is that 0x80 implies a filesystem.

I really don't see any harm in adding it, if you don't want to use it,
don't.

-- 
Brian C. Lane | Anaconda Team | IRC: bcl #anaconda | Port Orchard, WA (PST8PDT)

Re: [parted-devel] [PATCH 1/2] Add nonfs partition type 0xda (#1263835)

[Phil Susi]

On 10/9/2015 12:21 PM, Brian C. Lane wrote:
> I think their thinking is that 0x80 implies a filesystem.
> 
> I really don't see any harm in adding it, if you don't want to use it,
> don't.

I don't like adding things that serve no purpose and only confuse users.
 People end up running around with their hair on fire asking which type
they should use, and if it just doesn't bloody matter, why confuse them
and make the manual longer by giving them the choice?  Keep it simple.

To put it another way, seeing the option there makes people think they
need to use it for some reason, after all, why else would it be there?
And if that isn't true, then you have just created FUD.

Re: [parted-devel] [PATCH 1/2] Add nonfs partition type 0xda (#1263835)

[Brian C. Lane]

On Fri, Oct 09, 2015 at 01:23:24PM -0400, Phil Susi wrote:
> On 10/9/2015 12:21 PM, Brian C. Lane wrote:
> > I think their thinking is that 0x80 implies a filesystem.
> > 
> > I really don't see any harm in adding it, if you don't want to use it,
> > don't.
> 
> I don't like adding things that serve no purpose and only confuse users.
>  People end up running around with their hair on fire asking which type
> they should use, and if it just doesn't bloody matter, why confuse them
> and make the manual longer by giving them the choice?  Keep it simple.
> 
> To put it another way, seeing the option there makes people think they
> need to use it for some reason, after all, why else would it be there?
> And if that isn't true, then you have just created FUD.
> 

It does have purpose, as described in the bug. And most users won't pay
any attention to it. The vast majority of them care about 'boot' and
that's it.

-- 
Brian C. Lane | Anaconda Team | IRC: bcl #anaconda | Port Orchard, WA (PST8PDT)