Re: noaltroot bootparam [was Floppy Fallback]

From: Herbert P÷tzl (
Date: Wed Jul 23 2003 - 10:33:22 EST

On Tue, Jul 22, 2003 at 08:04:16PM +0100, John Bradford wrote:
> > Trond suggested to draft a patch to address the
> > Floppy Fallback issues (mentioned several times
> > on lkml) by adding a kernel boot parameter, to
> > disable the fallback, or to put it more general,
> > to disable alternate root device attempts ...
> >
> > Currently the NFS-Root Floppy Fallback is the
> > only _user_ of such a boot parameter, but in
> > future, this could be used to limit multiple
> > root situations to a make-or-brake ...
> >
> > please comment!

Hi John!

your comments are welcome,

> I think the best thing to do if it's not possible to mount an
> NFS-based root filesystem, is to wait 60 seconds, then try to contact
> the NFS server again.

I totally agree on that ...

> Before the in-kernel bootloader was removed, the current behavior was
> quite useful - it was quite possible that a hard disk-less machine
> would boot from a floppy without using a bootloader, and mount it's
> root filesystem from an NFS server. In this scenario, it would be
> impossible to boot the machine with the root on another device,
> without modifying the boot disk, so a fallback to root on a floppy was
> useful.
> However, the in-kernel bootloader was removed in 2.6, so there is now
> no reason why an alternate root couldn't simply be specified at the
> boot prompt.

hmm, sorry, obviously forgot to mention that the
patch is for 2.4.x ...

> If the NFS server is not accessible because of a temporary problem,
> (too much network traffic, or it's rebooting for example), it makes
> sense to try again after 60 seconds.
> Not trying the floppy should become the _default_ action.

this is something _I_ would prefer _too_, but on the
other hand there is tradition, and stable, and ... ;)


> John.
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

This archive was generated by hypermail 2b29 : Wed Jul 23 2003 - 22:00:49 EST