Uncompressed root fs to ramdisk.

[Mattias Sjogren]

After some minor initial problems we're now up and
running... Our only remaining problem is that mingetty does
not like to be run from the read-only disk. Init says that
it respawned too many times.

I have /var (inc a touched run/utmp), /tmp and /root as
mounted ramdisks. I boot of one big partition that I want
read-only.

/Mattias

Ralph Stickley <r_stickley@yahoo.com> skrev:
> Hi,
> 
> The solution I used to protect the system (copied from
> some other
> distributions):
> 
> Format the Compact Flash as follows:
> 1. hdx1 Create a boot partition (~1MB)
> 2. hdx2 Create a Read Only partition (~28MB)
> 3. hdx3 Create a Read/Write partition (~1MB)
> 
> Now load each partition:
> 1. hdx1 Copy boot.b and kernel-2.2.14 (or whatever your
> image is)
> 2. hdx2 Copy all files here
> 3. hdx3 format/erase
> 
> Now run LiLo and tell it where the boot image is
> (/dev/hdx1) 
> and where the file system is (root=/dev/hdx2)
> 
> Note fstab never has to mount the boot partition. All
> system files are
> maintained on the read only partition and never get
> corrupted. User files are
> vulenerable, but can be backed up on-to the Read only
> partition as required.
> 
> The trickery is all in rc.sysinit. At boot up, you have
> to mount everything
> and then load the default files to the read/write
> partition. This
> needs to be checked and reformatted if it gets corrupted.
> I also create a ramdisk to store the /tmp /var /whatever
> files in.
> this gives about 4MB of space to let the system store
> stuff.
> 
> 
> Some files on the Read Only partition may need to be
> updated on
> occasion.  A simple script will allow access to do this 
> (mount -o remount...).
> 
> So far, this works for me, doesn't take much ram.  I
> don't know how
> to get the permissions set properly, how to get the
> devices to work
> everytime and other little problems....
> 
> The applications I have working (on 32MB CF) so far:
> Netscape 4.7/Citrix/x3270/fvwm95
> 
> All system configuration is done through fvwm scripts
> (clock, mouse,
> keyboard, beep, network, startup applications, screen
> background).
> 
> Hope this helps,
> Ralph
> 
> --- Mattias Sjogren <mattias@voxway.com> wrote:
> > Hi all!
> > 
> > I have just got going with PeeWee Linux and it looks
> great
> > so far... My only problem is that I want to load the
> > uncompressed root filesystem to ram to avoid corruption
> on
> > sudden power failures. I know that this is easily done
> with
> > a compressed root fs but that makes it so hard to
> change so
> > I don't want that.
> > 
> > I'm booting from a 16MB Flash pcmcia card in an ide
> adaptor
> > using LILO. 
> > 
> > Another small question... How do I get the statup
> scripts to
> > automatically run fsck on the root fs? I have a '1' at
> the
> > right place in fstab but that doesn't help and I get no
> > errors...
> > 
> Don't know, I have the same problem...some option in
> mount I suppose...
> 
> 
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