Service OS is small Linux os which resides on USB/SDHC or hard disk partition. It can boot target platform individually. By combined with specific script upon, it can achieve various of purposes. Typical usage is on automated testing system, help do image auto-installation, HW health check.
Root file system of SOS can be gotten from any Linux Distros - Fedora, Ubuntu, MeeGo, etc. Below is a way to create SOS root file system from MeeGo
mic-image-creator --record-pkgs=name -P $prefix -S $suffix -c ./sos.ks -f loop --cache=./mycache
Mount fs: mount -o loop ${prefix}-meego-${suffix}.img $pmnt
Adjust run level: sed -i 's/id:5/id:3/' $pmnt/etc/inittab
Create grub configure file based on kernel and initrd under /boot
Assuming we have gotten root file system in last section as rootfs.tgz
dd if=/dev/zero of=$IMGFILE bs=512 count=$SECTORS
losetup $loopdev $IMGFILE
fdisk -u -C$C -H$H -S$S $loopdev <<EOF n p 1 a 1 p w EOF
mkfs.ext3 /dev/mapper/$part_name
mount /dev/mapper/$part_name $pmnt tar vxf $FS -C $pmnt/
grub --batch --no-floppy <<EOF device (hd0) $loopdev root (hd0,0) setup --stage2=$pmnt/boot/grub/stage2 (hd0) EOF
dd if=serviceos.IMG of=/dev/[USBDevice]