how to do a custom install?

Michael Powell nightrecon at
Sun Nov 15 10:09:57 UTC 2009

Gary Kline wrote:

> due to strange disk problems i was down for around 30 hours.  i am
> currently wiping dos/win off in favor of 7.2-R and i have a question
> about doing a "custom" install that would let me slice the drive into
> more that four pieces.
> i am building, by default,
> /,
> /var
> SWAP,  and
> /usr
> it has been years since my custom install where [[*some*]] technique
> let me slice something like, say,
> /,
> /var,
> /tmp,
> /usr/local/
> SWAP,  and
> /usr
> anybody remember what keys to hit in the installation procedure?
> tia,
> gary

Not sure about the terminology in use here. The old standard was to create 
one, or more, slice(s) and then partition with bsdlabel. In the sysinstall 
step for this it will run fdisk. Note that playing by the $MS standard the 
normal maximum number of slices would be 4, e.g. aka "primary partitions" in 
the Dos/Windows world. Fdisk makes "slices". An example of a slice on an IDE 
drive would be ad0s1.

After the fdisk step would next come bsdlabel. This is the step that creates 
partitions within the "slice" previously made with fdisk. Note the 
difference in terminology: what Dos/Windows refers to as a "primary 
partition" in the Unix world this is a "slice". 

Partitions are created within a slice with bsdlabel. On the sysinstall 
Custom menu these two options are one above the other, e.g. Fdisk and Label. 
Select the Fdisk and create a slice, exit fdisk returning to sysinstall and 
proceed to select the Label menu option to bring up bsdlabel. (IIRC also 
called disklabel.) 

An example of a partition would be ad0s1a, ad0s1b for swap, ad0s1c is a 
reserved wrapper entity, ad0s1d, e, f, g. Usually ad0s1a will be your root, 
b will be swap, d might be /usr, e might be /var. etc. In the bsdlabel 
utility there is the option to choose both the partition type and size as 
well as it's mount point. 

It is actually possible to have more than 4 slices even when playing by the 
$MS Dos/Windows standard. Fdisk will allow for the creation of what on Dos 
are called "extended partitions". The numbering for these starts at 5. You 
won't be able to boot from them and from a *Nix point of view are semi 
useless except within the context of Dos/Win compatibility.

If this is just going to be a FreeBSD machine no need for the so-called 
"extended partition" of the Dos/Win world. Just create a slice [fisk], and 
break that up into partitions [bsdlabel].

If everything goes according to plan after Fdisk, Label, Return to previous 
menu, etc, at some point later on (IIRC after choosing packaging 
distributions) sysinstall will later perform the actions you configure in 
these preparatory steps. For reference peruse the Handbook; it's probably 
written clearer than I can accomplish.


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