warning: code to do this actually isn't merged with master yet
This page describes creating a minix system on ramdisk, capable of being netbooted.
There are two parts. One, creating the hierarchy you want to have on the ramdisk, i.e. your eventual system. Two, creating the boot-time modules, containing the ramdisk with the full filesystem.
Use the DESTDIR feature of the buildsystem. The example hierarchy is
/usr/destdir, which initially doesn't exist at all. First create the skeleton hierarchy, then build world into it.
# make etcfiles DESTDIR=/usr/destdir # make world DESTDIR=/usr/destdir MINIXDYNAMIC=yes
Everything is built dynamically with
MINIXDYNAMIC=yes (not the default currently) to make the memory image significantly smaller.
The boot-time kernel and modules are the same as always, except that the bootstrap ramdisk is now a full filesystem.
# cd releasetools # rm ../drivers/ramdisk/image.memboot # make bootfiles MEMDESTDIR=/usr/destdir
MEMDESTDIR being set is what triggers the ramdisk contents being the specified hierarchy.
Set IMGFILESDIR to where you want the files to go; the default is the minix bootloader directory for
.memboot in the
releasetools/ source directory for
bootfiles. An interesting alternative is:
# make bootfiles MEMDESTDIR=/usr/destdir IMGFILESDIR=/usr/www/ipxe/
and let Minix netbooting clients netboot from your webserver.
Can be done using the builtin multiboot bootloader; no filesystem required:
$ kvm -m 800 -kernel kernel -initrd mod01_ds,mod02_rs,mod03_pm,mod04_sched,mod05_vfs,mod06_memory,mod07_log,mod08_tty,mod09_mfs,mod10_vm,mod11_pfs,mod12_init
unfortunately ipxe has to be recompiled to load more than 8 multiboot modules for now
To use iPXE to boot Minix straight from a PXE environment, use this ipxe script, thanks to the good folks at The iPXE project:
#!ipxe kernel kernel module mod01_ds module mod02_rs module mod03_pm module mod04_sched module mod05_vfs module mod06_memory module mod07_log module mod08_tty module mod09_mfs module mod10_vm module mod11_pfs module mod12_init boot
Save that script to your webserver, and put the boot modules and kernel in the same directory as the script. Then from kvm you can boot it out of the box:
$ kvm -m 800 -net user,bootfile=http://www.minix3.org/ipxe/minix3.ipxe -net nic,model=e1000
rm ../drivers/ramdisk/image.membootis necessary because a change in the full hierarchy can't easily be detected. So to make incremental makes painless, and a switch of ramdisk image build modes possible without using the wrong image, the memboot image isn't updated if it exists. So additional
make bootfilesinvocations will update the kernel and modules, but not the ramdisk contents, even if the hierarchy has changed.
MEMDESTDIRto your cross-
DESTDIR), you have to create the device nodes yourself manually first.