define more partitions in freebsd

[Polytropon]

On Sat, 1 Jun 2013 05:36:13 -0700 (PDT), Thomas Mueller wrote:
> > On Sat, 1 Jun 2013 11:10:32 +0430, s m wrote:
> > hello all
> >
> > > i want to install freebsd8.2 on my system. for some reasons, i need
> > > partitions more than 6. my freebsd just allow me to define partitions
> > > from a to h, not any more.
>         
> > That's correct and expected for the MBR partitioning approach
> > (which is considered "mostly outdated" today).
> 
> 
> 
> > > i checked FreeBSD handbook, but it doesn't say anything about defining
> > > more partitions.
> 
> > Because you _cannot_ define more partitions than up to 'h'.
> > This is a hard-defined limit of MBR-style partitions (as
> > they are initialized with bsdlabel).
> 
> 
> 
> > > my question is: how can i define more partitions on my freebsd? (for
> > > example, ad3s1a, ..., ad3s1h, ad3s1i, ad3s1j, ...).
> 
> > You cannot. You need to use the GPT partitioning approach
> > and repartition your disk. With gpart, you can create more
> > than 'h' partitions, but the partitions will have different
> > names, such as ad3s1p1, ad3s1p2, ..., ad3s1p10, ad3s1p11, ...
> > and so on.
> 
>         
> > Polytropon
> > Magdeburg, Germany
> > Happy FreeBSD user since 4.0
> > Andra moi ennepe, Mousa, ...
> 
> 
> Are you sure of this?  Can you GPT-partition an MBR slice as
> opposed to the whole disk?

Probably not. GPT "obsoletes" both slices and partitions.



> You should get ad3p1, ad3p2, ...,ad3p10, ad3p11, ...

That is what I should have written. :-)



> Then you would have to migrate an MBR partition table to GPT,
> if you have non-FreeBSD slices.  I don't know if gpart can do
> that, but Rod Smith's gdisk (included in FreeBSD ports) or
> gpt (still used in NetBSD but not FreeBSD) can.

The "simplest" approach would probably be to backup the
data from the existing partitions, re-inialize the whole
disk with a GPT scheme, format the (GPT) partitions and
then restore the dump previously taken. I'm not sure if
such kind of "harsh re-partitioning" can be done _safely_
on the fly...


-- 
Polytropon
Magdeburg, Germany
Happy FreeBSD user since 4.0
Andra moi ennepe, Mousa, ...