Jim,
Have you actually tried to use an initrd setup. Initrd is where the kernel
boots, unpacks a mini root filesystem in ram, it loads some modules etc
(e.g. the various usb modules) from there, then does a pivot root to new
root filesystem (say on the usb stick which it can now read with the
modules loaded) and continues with the "normal" boot from there.
there are several explanations on the web...
e.g. http://www.linuxforum.com/linux-filesystem/initrd.html
There is an example on the yahoo group web site
initrd_files.tar.bz2
An example initial ram disk and a ts7200 compressed kernel...
1113 KB dawydiuk
Jul 5, 2005
at
http://groups.yahoo.com/group/ts-7000/files/
cheers
Jim
On Thu, 6 Apr 2006 wrote:
> >...sorry for the soapbox
> Soapbox stuff is good. Even if I don't benefit from it (being too stupid,
> too stubborn etc), other readers might. Any information is good unless it's
> lies.
>
> I agree that Linux is Linux, be it big or small, and this is a big advantage
> in an embedded system. I'm selling that concept to customers.
>
> I can mount filesystems anywhere, but I've run into problems mounting
> /mnt/MyUsbFlash on / by doing a chroot which was the simplest way to get an
> nfsroot image to run locally from flash on this board. If I mount
> /mnt/MyUsbFlash on /usr, the problems I foresee is that Apache, mysql and
> php (6 modules in total that were installed by apt-get) may expect to see
> various bin, lib and etc configuration files. Maybe I should re-evaluate the
> assumption that it would be difficult to move those 6 modules to /usr or
> more appropriately /opt/lampp.
>
> An easier approach might be to copy-over the /etc stuff related to these 6
> modules and mount /mnt/MyUsbFlash/bin on /bin and likewise for any other bin
> and lib directories.
>
> Pointing Apache to something like /mnt/MyUsbFlash/www is easy. That's a
> matter of changing a config file under /etc.
>
> Any comments are welcome. If I had to articulate this as one question it
> would go like this: Assuming I have a working filesystem on an nfsroot, and
> I want to move that filesystem to the TS board so that it can boot
> stand-alone, and that filesystem is too big to fit in internal flash, how
> would you configure the system to boot and use that filesystem?
>
> Maybe get a different TS board with more boot-flash?
>
>
> -----Original Message-----
> From: On Behalf Of
> Jim Jackson
> Sent: Thursday, April 06, 2006 8:22 AM
> To:
> Subject: RE: [ts-7000] TS-7250 filesystem access before and after chroot
>
>
>
>
> On Thu, 6 Apr 2006 wrote:
>
> > Let me run my assumptions by you:
> > I have a working filesystem on an nfsroot that won't fit in on-board
> flash.
> > By "won't fit", I mean that a straight copy of all necessary directories
> > won't fit and it may cost more time than it's worth to try to copy only
> the
> > necessary files. If there's a fast way to determine the necessary files
> and
> > the size of those files then I can review my assumption that it won't fit.
> > It seems easy and quick to use /usr/bin/loadUSB.sh to 'switch-over' to usb
> > flash, but there appear to be side effects that are causing problems now
> and
> > will probably cause unforeseen problems. An alternative is to mount only
> the
> > bin directories and any other large directories over the internal flash
> bin
> > directories. I'm assuming that it will be a can of worms, or
> > stickingplaster, to change Apache2, mysql and php et. al. to run in a
> > directory structure different from the directory structure they where
> > 'apt-get-installed' into on the nfsroot.
> >
> > Thanks for your observations and input.
>
> Ok remember you can mount filesystems anywhere. In traditional unix
> systems many have '/' as a smallish partition, with another partition
> mounted as /usr, and another small one as /boot, and a large one as /home
> and maybe another as /var
>
> Also remember you can partition a usbstick - it doesn't have to be
> one filesystem. One can use fdisk to split it up into 2 or 3 partitions of
> suitable sizes. Each of the partitions can be mounted independantly
> in different places.
>
> You may be able to mount a usb stick partition under /usr to hold a lot of
> executables and libraries - you just need to make sure that everything
> needed to get to the point where the usb is usable are in /bin and /lib
> etc.
>
> Maybe you have a lot of web stuff under /www so you could mount another
> usb stick partition there.
>
> By doing this you integrate the on board flash and usb flash into what
> appears to be one seemless structure.
>
> HTH
> Jim
>
> p.s. I keep banging on about it being useful if you run Linux on your
> desktop/servers, because Linux is Linux whether it's on the TS7200
> or on a quad xeon dell server. What I've outlined above is pretty standard
> stuff for Unix system sysadmins, and it all applies to here too.
> (sorry for the soapbox stuff)
>
>
>
>
>
> Yahoo! Groups Links
>
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> Yahoo! Groups Links
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