Handbook Storage chapter

[Benjamin Kaduk]

On Mon, 4 Jun 2012, Warren Block wrote:

>> From a thread on -questions, the Handbook Storage chapter, in 
> disks/chapter.sgml, has some seriously outdated instructions.
>
> 19.3 "Adding Disks" talks about dedicated disks, an unnecessary 
> complication.

I have seen traffic on freebsd.org mailing lists within the past year from 
people using "dangerously dedicated" disks on recent-ish systems. Which is 
not to say that we need to mention it in the introductory paragraphs -- I 
do think that we should keep mention of it 19.3.2.2 and mention that it is 
not recommended, though.

>
> 19.3.1 suggests using sysinstall to slice and partition disks, a bad idea now 
> at least.  If you look at it funny, sysinstall will happily write the 
> /etc/fstab for the new disk over your existing one.  You didn't need that old 
> version, did you?
>

Agreed that advocating sysinstall for post-installation configuration 
should be removed.  Too bad that dteske's bsdconfig isn't in the tree yet, 
which would make our job easier.

> 19.3.2 has a procedure for setting up a disk using fdisk and bsdlabel, which 
> seems overly complicated, mounting the new disk at "/1".  At this point, use 
> of fdisk and bsdlabel can probably be replaced with gpart(8) instead.  At the 
> same time, the instructions for "dedicated" disks can be eliminated.  It has 
> no advantage and several possible disadvantages.
>

Given that the new installer defaults to gpart (most of the time?  I don't 
remember all the logic), I think it's okay to switch our documentation to 
it.  I think there are some purists who still want to use dedicated disks, 
and we can probably keep the one line about how to label a device directly 
with warning that your pointy hat should be sufficiently tall.

> Following that is a section on ccd(4), which needs a look.  I was under the 
> impression that ccd was, um, only historically relevant now.
>

Indeed.  ccd.4 and ccdconfig.4 both have .Dd in ... 1995.
In contrast to dedicated disks, I have not seen any ccd-releated traffic 
in recent memory.
Actually looking, Jeremy Chadwick gave it as an option in "File system 
trouble with ICH9 controller" on 6/10/10 (alongside ZFS, no less!)
More interesting is the 2009 thread "Request for opinions - gvinum or 
ccd?", which veered away with essentially "no, please use something else" 
(gstripe or ZFS).
The only thing I would want to check before applying the danish axe is 
that ccdconfig.8 mentions a mode for compatibility with Linux md(4) ... I 
would like to think that there are other ways to do this, but do not know 
offhand.

> Finally, there's a section on ataraid(4), which should at least mention and 
> link to the new graid(4) section in the GEOM chapter.
>

I think ataraid is really in a deprecated status.  The future is in ada(4) 
disks and not ad(4) disks, which means that ataraid(4) may not be used and 
graid(4) is necessary.
We should probably keep the ataraid(4) documentation for now but put a tag 
at the top that it is not current, per your suggestion.

> 19.10 "Backups to Floppies" can probably go.  It wasn't very viable even when 
> floppies could still be bought.

Staples will sell me ten (10) 3.5" floppy disks for $1.19 ... they're not 
dead, yet.
But, please do remove this section.  I don't think one can even fit a 
FreeBSD kernel on a single floppy these days.

-Ben