Subject: Re: Migration question( OpenBSD 2.9 -> NetBSD -current)
To: Luke Mewburn <>
From: Milos Urbanek <>
List: current-users
Date: 05/02/2002 11:37:50
On Thu, May 02, 2002 at 09:47:14AM +1000, Luke Mewburn wrote:

>   | My experience is that although NetBSD and OpenBSD use ffs fs, there are
>   | some subtle differences that cause the NetBSD not to be able to mount ffs
>   | partitions created under OpenBSD.
>   | More specifically, under NetBSD current (e.g. 1.5ZC) you can mount
>   | ffs partition from OpenBSD 3.0, but when you do a 'ls' or another
>   | fs operation on it you will get an EBADF error if I'm correct.
> This is interesting.  Do you have any further details?  Does NetBSD
> current's fsck_ffs (with -n to "not change" the file system) work
> on the OpenBSD ffs partitions?

Ok. I will put my disk with NetBSD 1.5ZC in the machine with
2 disks with OpenBSD 3.0 ffs partitions and try to elaborate a bit around

I remember that when I was installing NetBSD 1.5ZC on my computer I
had there one OpenBSD ffs partition from OpenBSD 3.0. When I tried
to run fsck on the partition it dumped a core after receiving a signal
I already do not remember the failure message but it was something that
contained substring "floating point operation".
(I don't remember right now the exact details but I will have a closer
look at it and I will try to send you more specific details.)
I solved this by running NetBSD newfs at the partition..

> A while ago I took pains to ensure that the ffs superblock in NetBSD
> would be compatible with FreeBSD's and OpenBSD's, so that explains why
> the mount worked ok.  I also took a brief look at other changes in ffs
> on those systems at the time and I don't recall anything that would be
> done to make things difficult.
> If possible, I would like for NetBSD to be able to mount FreeBSD and
> OpenBSD ffs partitions (there really should be no need for gratitious
> incompability here, especially if we're not using newer features such
> as snapshots on the partition, as all three systems are relatively
> "close" in this way), and possibly other platforms such as MacOS X,
> Solaris, etc.

>   | Therefore I would suggest you to do a full backup (e.g. using tar) and than
>   | reinitialize your disks by fresh NetBSD-like raid/ffs partitions.
>   | 
>   | Milos
> -- 
> Luke Mewburn  <>
> Luke Mewburn     <>
> Wasabi Systems - NetBSD hackers for hire
> NetBSD - the world's most portable UNIX-like operating system