Active slice, only for a next boot

[rank1seeker at gmail.com]

----- Original Message -----
From: Julian Elischer <julian at freebsd.org>
To: rank1seeker at gmail.com
Cc: hackers at freebsd.org, Doug Ambrisko <ambrisko at freebsd.org>
Date: Sat, 28 May 2011 11:07:05 -0700
Subject: Re: Active slice, only for a next boot

> On 5/28/11 6:06 AM, rank1seeker at gmail.com wrote:
> > And how about this:
> >
> > # boot0cfg -o noupdate -s 1
> > Now when you choose to hit slice 2, it is only for a this one boot.
> > Next and each boot, defaults to slice 1
> >
> > Problem is, that you must see, early bootstrap, to manually choose, so this won't work on a remote server.
> > This requires:
> > a) physicall access
> >     or
> > b) ssh access to the remote box, which is conected via serial cable, to your server.
> >
> > Anyone has any idea, for a case of a remote server, which is accessible over ssh, only when it is "up"?
> 
> pull the old bootblocks from about 2000 and use them.
> and nextboot as well
> they do exactly what you want.
> 
> OR
> 
> ask Doug Ambrisko (cc'd) for a copy of them that he still uses at work.
> He may have updates to make them work with modern systems that would 
> save you time.
> 
> the old nextboot(8) stored instructions as to what to do on block 1 of 
> the drive
>   (you can make it a small 1 block partition if you want). Actually it 
> stored a series of them, NULL separated.
> On each boot the boot 0 bloter would read the first (after skipping 
> any nulls) and then write Nulls over
> what it just read and write it back to block 1.
> so it would progress gradualy boot by boot over the sequence written 
> by nextboot.
> 
> it would pass on the stack, what it had read to boot1.
> 
> 
> the format was "hd(1,a)/boot/loader"    (for example)
> personally I would like to hav ethis capabiltiy back because it's 
> stupid  rely on a
> possibly dead filesystem to get around booting from the possibly dead 
> filesystem.
> 
> by default we used to have a /etc/rc entry that would rewrite the 
> 'current' setup several times on successful boot,
> followed by a couple of alternate boot targets.
> If boot failed a coupke of times it would automatically boot from the 
> second drive or from another partition,
> ..
> 

Well, if he has a working code and you have an idea, then it should be modernized and integarted into FreeBSD's src tree.
So everyone could use it.

> 
> 
> >
> > Domagoj Smolčić
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> >
> >
> 
>