Re: Readying a disk for booting NetBSD-5

[Eduardo Horvath <eeh%NetBSD.org@localhost>]

On Fri, 4 Jun 2010, DL wrote:

> Eduardo:
> By the way... Sad Cloud's reply at
> http://article.gmane.org/gmane.os.netbsd.general/28714 got me to wondering... 
> is
> the 5.9 bootloader limitation to the FFSv1 filesystem that you clarified here
> actually specific to the sparc64 port?  Or does the same apply to the
> bootloaders installed with i386 and/or other ports as well?

Different bootloaders use different methods to locate file blocks on disk.  
The 32-bit SPARC port encodes the 2nd level booter's blocks in the 
bootblock as part of installboot.  I think x86 uses a similar method.  The 
SPARC64 boot block has filesystem reader code.

The advantage of using a set of disk addresses in the bootblock is that it 
doesn't need to know the filesystem layout so you can boot off just about 
any filesystem.  However, if the filesystem ever moves those blocks, like 
the LFS may, the machine may spontaneously stop booting.  YMMV.

Eduardo