Optimising pxeboot disk size

[Da Rock]

On Tue, 2008-12-16 at 15:02 +0100, Bernard Dugas wrote:
> Wojciech Puchar wrote:
> > i already did such things but with NetBSD 1.5 for my Xterminal distro.
> > 
> > it's simple:
> 
> More simple when you tell it ;-) Thanks a lot, i will try it tonight !
> 
> > I wish it's helpful, doing this doesn't just save space but saves time - 
> > you have to upgrade software once.
> 
> So preserving consistency, which is the most important when you have lot 
> of diskless stations !
> 
> > you may like to make /etc-common directory and put most of files there, 
> > and symlinks in each station's /etc
> 
> In fact, it makes me think that we miss a concept in mount, or at least 
> i don't know it currently :
> imagine a -tl (TransparentLayer) option for mount, allowing to mount 
> multiple source to the same directory, for instance /etc :
> 
> mount -r yournfsserver:/basic/etc /etc
> mount -tl -r yournfsserver:/TypeX/etc /etc
> mount -tl -r yournfsserver:/StationY/etc /etc
> 
> A file is first look for in yournfsserver:/StationY/etc,
> then in yournfsserver:/TypeX/etc
> and finally in yournfsserver:/basic/etc.
> 
> This means that StationX will see in its /etc firts its specific files, 
> then the files dedicated to TypeX station (webserver, dns server, 
> workstation,...) and then all basic files unchanged from standard 
> distribution.
> 
> When you want to change something, you add a rw TransparentLayer :
> mount -tl yournfsserver:/StationYchanges/etc /etc
> 
> So that changed or added files are only stored in this rw partition, 
> thus very small and easy to manage.
> 
> This would be a kind of partition inheritance, like in object 
> languages... Dreams are allowed :-)

Apparently that sort of thing is available on plan9 OS. Everything is a
file so you can mount remote and local devices- plus merge them in a
single directory. Check it out on wikipedia...

Dreams can come true! :)