Re: MythTV frustration.

Lance Levsen wrote:
> Yes. That would probably be the easiest in a home network. Test with
> floppy before you flash the NIC's ROM or burn to CD. I've found that it
> takes _a lot_ of trial and error to find the correct ROM for any
> particular NIC. When you are testing, don't assume your custom configs
> are broken, assume the ROM incorrect for your NIC.
>

You know, I honestly don't own any floppy devices. I haven't had one
connected in a machine in 6 years, excepting when I had to flash a BIOS
a year ago (and that was only do-able because of Scott's collection of
older bits :)). Booting from CDROM could work as a test.

On reading the etherboot wiki, I was under the impression that I could
first feed the PXE rom-o-matic image to my card's PXE loader (stage 0),
and then that would executed as stage 1 which would get the full kernel
and start it up with NFS root/swap.

Something like this:
http://www.etherboot.org/wiki/pxe2ndstage

My Intel NICs all support PXE natively w/o the need for option ROMs.

> Even 10BaseT is sufficient to push the kernel over, I'm not sure how you
> are going to pivot root though, I didn't see any options for that in the
> custom Etherboot options. Nor do I think you can compile in a root path
> to the kernel. That's one of the reasons I use DHCP for this; option
> root-path "192.168.56.1:/opt/ltsp/i386"; makes life easy.

Steven's comment about using initrd seems to be the way to go. Give the
kernel + a minimum environment in an image to the PXE loader, something
that's enough to initialize itself to be an NFS client.

> I don't do this manually, and instead rely on LTSP to set it up. I would
> imagine though that you need to create a swap, and then set it up via
> nfs in your thins /etc/fstab and in the boot scripts. LTSP uses a
> network block device and a daemon on the server to offer swap though, so
> there may be monsters. I can send you the init script from the clients
> if you want. They may be helpful. HOW-TO's on creating custom rescue
> discs might help here too.

I think I'll have to experiment with using ndb and raw swap to see what
  works best. Linux used to be able to swap to a file, which would be
the path I'd expect this kind of swap to take.

>
> I'm guessing that when you enable NFS in the Etherboot ROM, and
> customize the static options, the STATIC_BOOTFILE is probably the kernel
> image.

Yea. I can configure my DHCP server to hand back either the PXE loader
or a real kernel image name, per:
http://www.etherboot.org/wiki/pxefilenamehack

> No problem w/ NFS and XFS. Most of our NFS mounts are XFS. You won't
> have an issue. We use it because XFS is better for large amounts of
> smaller files compared to ext3 and the Posix ACL's are fully compatible
> with samba. The latter won't matter to you though.

Actually, it'd make the one share I have that's shared out via SMB (to
VMware and Xbox Media Center, which speaks SMB to get movies/etc) happier.

> Use this package if you want to use the kernel-mode NFS server. The
> user-mode NFS server in the "nfs-user-server" package is slower and less
> featureful but easier to debug than the kernel-mode server.

It looks like I'm using the kernel server, given the man page describes
it as just the front end for a kernel nfs.o thread.

> Heh, got burned on the large packets with a 3Com4200 switch. Took me a
> while to figure out that the Quality of Service default configurations
> were fragmenting the NFS packets on the GBit ports. Very annoying,
> 100BaseT worked fine, just not the Gigs until we turned off QOS. Then
> everything screamed. That affected AFP too. I think it's dumb for 3Com
> to default their switches to standard TCP packet size.

Migrate to IPv6 -- no more packet fragmentation ;)

> This maybe your easiest option. I've never made a bootable USB as none
> of our machines are new enough to have that as a boot option in their
> ROM. That might be fun too. :)

I was thinking it shouldn't be too hard to prepare such an image.
VMware lets me use raw disk partitions, so I could setup an install of
something and have it treated like a real disk, then take it over to the
machine and boot it. I could easily backup/restore the image. If 512mb
is too cramed, I have a 2gb memory key I use periodically that could be
used for thetask (the 15$ 512mb keys would do for most of what I've been
using the 2gb key for).

I was thinking the best way to go about it would be:
  - Ubuntu 6.10 server install (no desktop crap, like 250mb of
OpenOffice!, no Gnome, etc).
  - Stick on Myth, MySQL, Apache, ratpoison.
  - Done!

The current setup (which does have the Gnome albatross, as well as a lot
of random Python packages) weighs in at 2.9gb for the /. Since
MySQL/Apache/etc would all have their data stored via NFS, the only real
cost is the base installation.

I'm going to apt-get remove things from my current install to see what
happens.
Received on Sun Nov 5 11:39:11 2006