[Gb-ccb] Backup of the CCB microdrive

[John Ford]

This is too much trouble.  We'll just take off the lid :)

John

>
> On Fri, 14 Oct 2005, John Ford wrote:
>>...
>> Maybe we could network boot it?
>
> I've spent this afternoon looking into this possibility. The GRUB
> boot-loader has the capability to boot over the network, although
> setting this up would take some work. It would involve the following
> steps:
>
> 1. The version of GRUB that comes with Fedora doesn't enable network
>     booting. Thus I would need to recompile and reinstall grub. I
>     downloaded the source code this afternoon, and verified that it has
>     a network driver and corresponding configuration option that should
>     support the network interface on the CCB computer. Basically I
>     would do the following, in the directory of the GRUB source-code
>     distribution:
>
>       ./configure --enable-natsemi
>       make
>       make install
>       grub-install
>
>     I don't want to do this unless we agree that we want to go ahead
>     with network booting, because if there is any problem with the
>     installation of grub, then the system could become unbootable.
>
> 2. We would need to make the kernel etc available on an NRAO computer,
>     via TFTP. This brings up 3 questions:
>
>      A. Would NRAO's security policy allow this?
>      B. Can one make a mounted CD (ie a live CD like Knoppix) available
>         via TFTP, or would we have to copy the contents of the CD to a
>         TFTP area first?
>      C. Do live CDs like Knoppix contain the normal kernel files etc, or
>         do they have some custom compression/decompression scheme that
> would
>         flummox GRUB?
>
> 3. To actually start a network boot, without having to take the lid
>     off the CCB to connect a monitor and keyboard, we would need access
>     to the GRUB boot screen, via the serial COM port.
>
>     I have been investigating this as well. The most convenient method
>     would have been to get the BIOS to redirect all console output to
>     the COM port. Some BIOSes do support this, but I just got a reply
>     to my query about this to Lippert, and they told me that the BIOS
>     on the Cool Roadrunner III CPU-board, doesn't support console
>     redirection. They told me that it might be possible to add this,
>     but that if we wanted this, then we should talk to their sales
>     department. ie. It would cost more money.
>
>     Since the BIOS can't do console redirection, we won't be able to
>     interact with the BIOS screens from the COM port, and will have to
>     take the lid off the CCB if we ever want to fiddle with the BIOS.
>
>     However, the lack of console redirection doesn't prevent us from
>     redirecting console messages to the COM port, once the boot-loader
>     has taken over control from the BIOS. This can be done by adding
>     configuration lines like the following to the
>     GRUB configuration file (/etc/grub.conf):
>
>      serial --unit=0 --speed=9600 --word=8 --parity=no --stop=1
>      terminal --timeout=10 serial console
>
>     We will need to hook up a VT100-compatible terminal emulator,
>     configured as above, to check that this works.
>
>     If a terminal emulator that isn't VT100 compatible, is used, then
>     we would instead have to use:
>
>      serial --unit=0 --speed=9600 --word=8 --parity=no --stop=1
>      terminal --timeout=10 --dumb serial console
>
>     I'm putting off trying this until somebody has time to hook up a
>     terminal emulator to the COM port on the front panel of the CCB.
>
> 4. I would add a menu entry to the Grub configuration file, to allow
>     the selection of the network boot. This would look something like:
>
>      Title Network Boot
>      # Get an IP address for the CCB computer.
>      dhcp
>      # Assuming that the DHCP server doesn't tell us the TFTP server's
> address,
>      # we then need to explicitly specify this.
>      tftpserver 192.33.116.whatever
>      # Tell GRUB that the root-directory is to be accessed over the
>      # network device.
>      root (nd)
>      # Tell Grub the name of the kernel image on the TFTP server, and
>      # tell the kernel not to use DMA with the microdrive, or ACPI.
>      kernel /vmlinuz-2.6.12-1.1398_FC4 ro root=LABEL=/ ide=nodma acpi=off
>      initrd /initrd-2.6.12-1.1398_FC4.img
>
> So. Is it worth setting up network booting, and when would it be
> possible to try out the console-redirection to the COM port, with a
> terminal emulator?
>
> Martin
>