Re: adding newfs_ext2fs and mount_ext2fs to ramdisk flist

[buhrow%lothlorien.nfbcal.org@localhost (Brian Buhrow)]

        Hello.  I don't know if it's a lot of trouble, but I wonder if you try
building a filesystem with -O 0 for pv-grub to boot from rather than ext2fs
if you will get success?  If so, then you can hav ffs on all filesystems
and not have to make the requested change.  Plus, it means you can make
things work  with the existing releases.  The -O 0 flag tells newfs to
creat 4.3BSD compatible filesystems.  These are compatible with 20 year old
Sun ROM code, so if pv-grup can understand ffs/ufs filesystems at all, I'm
guessing it can definitely understand 4.3BSD filesystems.
-Brian

On Jun 17, 11:20am, Blair Sadewitz wrote:
} Subject: Re: adding newfs_ext2fs and mount_ext2fs to ramdisk flist
} On Sun, Jun 17, 2012 at 10:36 AM, Greg Troxel <gdt%ir.bbn.com@localhost> 
wrote:
} >
} >
} > If they are added, it seems i386 and amd64 should both get them.
} > How much more space is needed?
} 
} Umm, I don't think much. ;-)
} 
} >
} > It sounds like {mount,newfs}_ext2fs are needed to set up a small
} > partition to store the pvgrub config/kernel, and then you are using ffs
} > for NetBSD to use as a real partition.
} >
} Well, that is what a lot of people do.  My particular provider uses
} file-backed disks in lvm; the disk is /dev/xvda1 in linux (there is no
} xvda).
} 
} > Did you consider just using ext2fs for the entire netbsd disk? =C2=A0As a
} > long-time BSD user, that feels odd, but I wonder if people have
} > opinions/data on how well it works
} 
} I would rather use ffs, considering that it does work. ;-)
} 
} > I've had the impression ext2fs had
} > consistency issues with unclean shutdown, but also that those were fixed
} > in Linux, and of course our code is different.
} >
} > As for ffs/ufs, it is confusing, but basically "-O 2" leads to
} > UFS2/FFSv2. =C2=A0 FFSv1 can have various sublevels; see -c option to
} > fsck_ffs. =C2=A0It is common to use -c 5 which leads to ufs2-style
} > superblocks in a ffsv1 layout.
} 
} I'm not positive, but IIRC, I tried going to level five and it didn't
} boot anymore.
} >
} > dumpfs is helpful; it will show you the fs-level magic number and the
} > superblock format, and a fs level.
} 
} Yeah, I figured that out somewhere along this enchanted journey of linuxnes=
} s.
} 
} >
} > i think 'newfs -O 1' leads to the same as fsck-ffs -c 4, but I'm not
} > sure.
} I think that is what happens.
} >
} > You said pvgrub can read ffsv1. =C2=A0Do you know if that's with ufs2
} > superblocks, or the older superblocks, and what the version of pvgrub
} > is?
} >
} 
} That is with whatever sysinst does when you choose ffs2.  I am unsure
} of the version of pv-grub.  I only just found its repository the other
} day. ;-)  I think that also happens if you choose to go to level 5, as
} I mentioned above.
} 
} > I don't know of any compelling reasons to use ufs2 vs ffsv1 for smallish
} > filesystems (where smallish is certainly up to tens of GB).
} >
} I don't really, either, other than it was the default and I am trying
} to make this as painless as possible for everyone. ;-)
} 
} > I tend to use ffsv1 (with v2 superblocks) for root filesystems, and ufs2
} > for the bigger data ones.
} 
} Well, my whole filesystem is 'only' 40GB.  Should I just not care?  I
} haven't even been using multiple slices yet, heh, because I don't even
} know what I'm going to end up using.  If you have any suggestions for
} a layout, though, I'll take note. ;-)
} 
} Regards,
} 
} --Blair
>-- End of excerpt from Blair Sadewitz