Diskless boot

The Linux SCSI Target Wiki

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iSCSI is an ideal protocol for diskless boot. Here's a HOWTO describing how to set that up.

Contents 1 Client 2 Server 3 Boot time 4 See also 5 External links

Client

• Download and setup Core-iSCSI and the Core-iSCSI-Tools (the test system was setup wih Linux kernel 2.6.14.5)
• Setup ISC DHCP (dhcp-4.2.0.tar.gz)
• Edit /etc/dhcp/dhcpd.conf:

allow booting;
allow bootp;
option routers 192.168.1.6;
option subnet-mask 255.255.255.0;
ddns-update-style ad-hoc;
subnet 192.168.1.0 netmask 255.255.255.0 {
   range 192.168.1.111 192.168.1.115;
}
group {
   next-server 192.168.1.6;
   filename "pxelinux.0";
   host laptop-eth0 {
       hardware ethernet 00:00:00:00:00:00; (replace with your mac-address)
}

• Setup PXELinux (syslinux-4.03.tar.bz2)

• Untar and install

untar syslinux, make && make install
untar tftp-hpa, make && make install
mkdir -p /tftproot/pxelinux.cfg
cp pxelinux.0 /tftproot

• Build a kernel for your client and copy it to /tftproot/
• Make an initrd and copy it to /tftproot
• Edit /tftproot/pxelinux.cfg/default:

TIMEOUT 50
PROMPT 1
LABEL iscsiboot
KERNEL vmlinuzLaptop
APPEND root=/dev/ram initrd=bblinux25M
IPAPPEND 1
LABEL disk
LOCALBOOT 0

• Setup TFTP-HPA (tftp-hpa-0.41.tar.gz):

tar zxvf tftp-hpa-0.41.tar.gz
cd tftp-hpa-0.41
./configure
make
make install

• And finally start the tftpd:

/sbin/in.tftpd -l -v -s /tftproot

Server

• Setup an LinuxIO and some test disk.
• Setup a PXE server (this includes ISC DHCP, syslinux and TFTP-HPA):

wget http://linux-iscsi.org/iscsiboot/server-scripts/pxeserver-setup.sh

Boot time

• Change BIOS on client to "pxeboot before HD".
• At the pxelinux prompt, type iscsiboot (referring to label in pxelinux.cfg/default).

After successfully booting, do something along these lines:

/bin/mount / -o rw,remount
/bin/mount -t proc none /proc
/bin/mount -o sysfs /sys
/sbin/ifconfig eth0 192.168.1.92 255.255.255.0
cd /dev && /bin/mknod sdb1 b 8 17
NAME=$(/sbin/initiator-iname)
echo "InitiatorName=$NAME" > /etc/initiatorname.iscsi
/etc/rc.d/init.d/initiator start

If this is a new installation, partition and create a file system, then copy minimal files to your new disk

/bin/fdisk /dev/sdb # (create partition)
/bin/mke2fs /dev/sdb1
/bin/mount /dev/sdb1 /laptop:diska
cp -dpRav /bin /sbin /dev /etc /var /lib /usr /tmp /laptop:diska

• And, lastly:

/bin/chroot /laptop:diska /bin/bash

See also

• Core-iSCSI
• LinuxIO

External links

• Diskless server installation (iSCSI boot install)
• iSCSI-boot-admin
• iSCSI RPM repostory
• Etherboot