Linux Booting in Rescue Mode with PXE

APPLIES TO:

Linux OS – Version: 4.4 to 5.3 – Release: OEL4U4 to OEL5U3
Linux x86
Linux x86-64

GOAL

To be able to boot into Rescue Mode with PXE

SOLUTION

Requirements

• DHCP Server
• TFTP Server
• HTTP Server

In the following Example the dhcp, tftp and http server is 192.168.79.110. The server that should be booted with PXE has the MAC Address: 00:16:3E:53:17:D7

Configuration

1. add the following entry into your dhcpd.conf
   host pxetest {
hardware ethernet 00:16:3E:53:17:D7;
next-server 192.168.79.110;
filename "/el4u5/pxelinux.0";
}


   – restart the dhcpd server

2. kickstart config ( in /var/ww/kickstart/ks.cfg ):
   lang en_US.UTF-8
langsupport --default=en_US.UTF-8 en_US.UTF-8
keyboard us
mouse none
url --url http://192.168.79.110/el4u5/
network --bootproto=dhcp

3. mount an Enterprise Linux iso file
   # mount -o loop Enterprise-R4-U5-i386-dvd.iso /var/www/el4u5
4. copy all necessary files to /tftpboot/el4u5
   # up2date syslinux
# mkdir /tftpboot
# mkdir /tftpboot/el4u5
   # cp /usr/lib/syslinux/pxelinux.0 /tftpboot/el4u5
   # mkdir /tftpboot/el4u5/pxelinux.cfg
   # touch /tftpboot/el4u5/pxelinux.cfg/default
   # cp /var/www/el4u5/images/pxeboot/* /tftpboot/el4u5/

5. configure /tfpboot/pxelinux.cfg/default entries:
   default linux
   timeout 100
   prompt 1

   LABEL linux
KERNEL vmlinuz
APPEND initrd=initrd.img ramdisk_size=10000 text rescue ks=http://192.168.79.110/kickstart/ks.cfg


6. httpd config ( not necessary if you already have a running httpd )
   DocumentRoot "/var/www"

   # This should be changed to whatever you set DocumentRoot to.
#
<Directory "/var/www">
Options Indexes FollowSymLinks
AllowOverride None
Order allow,deny
Allow from all
</Directory>


   – start httpd

   # /etc/init.d/httpd start
7. tftp server
   – install tftp server
   # up2date tftp-server


   – enable the tftp server

   # /sbin/chkconfig --level 345 xinetd on

   – in /etc/xinetd.d/tfpt change

   "disable = yes"

   to

   "disable = no"

   – restart xinetd

   # /etc/init.d/xinetd restart


   Now your client 00:16:3E:53:17:D7, if pxe boot enabled, will boot into Rescue Mode.