misc/179312: PXE installer fails to boot without modification

[Antoine Beaupre]

>Number:         179312
>Category:       misc
>Synopsis:       PXE installer fails to boot without modification
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Tue Jun 04 20:30:00 UTC 2013
>Closed-Date:
>Last-Modified:
>Originator:     Antoine Beaupre
>Release:        FreeBSD 9.1-RELEASE amd64
>Organization:
Koumbit.org
>Environment:

-rw-r--r--  1 root   root    153296896 mai 29 17:02 FreeBSD-9.1-RELEASE-amd64-bootonly.iso

SHA1:

2038a484ffeea3225e6d91bb1488e2548ac173bb  FreeBSD-9.1-RELEASE-amd64-bootonly.iso

>Description:

There used to be a way to install FreeBSD through a PXE bootloader. That
bootloader is still present in the ISO and while the article itself has
disappeared (http://www.freebsd.org/doc/en/articles/pxe/article.html), I assume
that this capability was not lost in the 9.x series.

PXE-based installs do not work out of the box in 9.1 anymore, a regression from
8.1 at the very least.

>How-To-Repeat:

Follow those instructions:

http://freebsd.so14k.com/freebsd9_pxe.shtml

>Fix:

As you see in the above instructions, the user needed to comment out the
following line in /etc/fstab:

/dev/iso9660/FREEBSD_INSTALL / cd9660 ro 0 0

... otherwise the boot fails. Having to modify that file means we need to
duplicate all those files instead of being able to simply mount the ISO as a
filesystem and offer it over NFS...

But even then, this seems just like a crude workaround to a wider problem: in
8.1, the .ISO could be loaded directly into memory and boot properly through a
local memory filesystem.

That way, the .iso could be loaded directly from syslinux, for example with
pxelinux and memdisk:

LABEL FreeBSD-8.1-i386
        MENU LABEL FreeBSD 8.1 i386
        kernel memdisk
        append initrd=freebsd/FreeBSD-8.1-RELEASE-i386-bootonly.iso iso raw

This doesn't work in 9.1 anymore, probably because the mfsroot file seems to be
gone from 9.1.

All this makes PXE-based FreeBSD deployments *much* harder and less attractive
than before, because we need to setup a separate NFS server and hack at the
files.
>Release-Note:
>Audit-Trail:
>Unformatted: