Net Boot

[Aaron Hanson]

Hi All -

I didn't get any responses on my question earlier in the week, so I
just forged ahead. I'm trying to get a net-boot of the complete livecd
image. I've been merging the isolinux/initrd.img with the entire
squashfs os.image and sending it to the target device with 'pxelinux'.

The kernel loads, and the initrd is dutifully transferred, but I
think I'm building the initrd wrong, because the kernel can't figure it
out (see below). Does anybody have some tips on the correct way to
construct the initrd? Thanks...

-Aaron

Loading vmlinuz.lcd..................................
Loading
initrd.img.lcd..........................................................
Ready.Run Diagnostics
Linux version 2.6.21-1.3116.fc7
([e-mail]) (gcc 7
BIOS-provided physical RAM map:or
...
...
checking if image is initramfs...<6>Switched to high resolution mode on
CPU 0
it isn't (no cpio magic); looks like an initrd
Freeing initrd memory: 98747k freed
...
...
md: ... autorun DONE.
RAMDISK: Compressed image found at block 0
RAMDISK: incomplete write (-28 != 32768) 16777216
isofs_fill_super: bread failed, dev=md1, iso_blknum=16, block=32
No filesystem could mount root, tried:  iso9660
Kernel panic - not syncing: VFS: Unable to mount root fs on
unknown-block(9,1)

[Cain, Brian (GE Healthcare)]

> -----Original Message-----
> From: [e-mail] 
> [mailto:[e-mail]] On Behalf Of 
> Aaron Hanson
> Sent: Friday, May 11, 2007 12:32 PM
> To: [e-mail]
> Subject: [Fedora-livecd-list] Net Boot
>
> Hi All -
> I didn't get any responses on my question earlier in the 
>
> week, so I
> just forged ahead. I'm trying to get a net-boot of the complete livecd
> image. I've been merging the isolinux/initrd.img with the entire
> squashfs os.image and sending it to the target device with 'pxelinux'.
> The kernel loads, and the initrd is dutifully transferred, but I
>
> think I'm building the initrd wrong, because the kernel can't 
> figure it
> out (see below). Does anybody have some tips on the correct way to
> construct the initrd? Thanks...

I would try mounting the squashfs image via NFS or tftp.  You can hack
up the livecd-creator to offer you a boot option that includes a "root="
arg.  In fact, I would think it might be easier to mount an
(uncompressed, simple) NFS root than an image file.  Maybe you could
manually unpack the squashfs image to somewhere you're exporting.

This is by no means something that works, but it might help you get the
ball rolling (patched livecd-tools-008-1, iirc):

--- /usr/bin/livecd-creator     2007-05-07 16:07:33.000000000 -0500
+++ nfs-livecd-creator  2007-05-11 12:42:17.068968000 -0500
@@ -858,6 +858,12 @@
 """ %{"label": self.fs_label, "background" : have_background,
       "short": short, "long": long, "extra": extra}

+        cfg += '''label nfs
+    menu label NFS boot
+    kernel vmlinuz
+    append initrd=initrd.img root=/dev/nfs rw
nfsroot=12.345.67.89:/path/on/server/to/nfs_root ip=dhcp console=ttyS1
+'''
+
         cfgf = open("%s/out/isolinux/isolinux.cfg" %(self.build_dir,),
"w")
         cfgf.write(cfg)
         cfgf.close()

-Brian