PXE-Boot on RHEL-6

. Use Yum utility to Install required rpm
#yum install dhcp tftp-server syslinux httpd nfs-utils system-config-kickstart bind-*

2. Configure Dns server for host name resolution

#cp -p /etc/named.* /var/named/chroot/etc

#cp -p /var/named.* /var/named/chroot/var/named


#rm -rf /etc/named.*

#rm -rf /var/named.*

#cd /var/named/chroot/etc

#vim named.conf
options {
listen-on port 53 { 127.0.0.1; 192.168.0.254; }; <= Define here the ip of dns
listen-on-v6 port 53 { ::1; };
directory
"/var/named";
dump-file
"/var/named/data/cache_dump.db";
statistics-file "/var/named/data/named_stats.txt";
memstatistics-file "/var/named/data/named_mem_stats.txt";
allow-query { localhost; any; };
recursion yes;
dnssec-enable yes;
dnssec-validation yes;
dnssec-lookaside auto;
/* Path to ISC DLV key */
bindkeys-file "/etc/named.iscdlv.key";
managed-keys-directory "/var/named/dynamic";
};
logging {
channel default_debug {
file "data/named.run";
severity dynamic;
};
};
zone "." IN {
type hint;
file "named.ca";
};
zone “example.com” IN {                 <= Here declare the forward zone
type master;
file “for.zone”;
};
zone “0.168.192.in-addr.arpa” IN {   <= Here declare reverse zone
type master;
file “rev.zone”;
}
:wq

#cd /var/named/chroot/var/named

#cp -p named.localhost f.zone

#cp -p named.loopback r.zone

#vim f.zone
$TTL 1D
@
IN SOA server1.example.com. root.server1.example.com. (
                                                   0;                      serial
                                                   1D;                   refresh
                                                   1H ;                  retry
                                                   1W;                   expire
                                                   3H ) ;                minimum
                     NS      server1.example.com.
server1         A        192.168.0.254
desktop1       A        192.168.0.1
desktop2       A        192.168.0.2
desktop3
:wq

#vim r.zone
$TTL @  IN SOA  server1.example.com. server1.example.com. (
                                                    0;               serial
                                                    1D;            refresh
                                                    1H ;           retry
                                                    1W;           expire
                                                    3H ) ;        minimum
                             NS     server1.example.com.
254                      PTR    server1.example.com.
1                          PTR    desktop1.example.com.
2                          PTR    desktop2.example.com.
3                          PTR    desktop3.example.com.
:wq

#chkconfig named on ; /etc/init.d/named restart
2. Now Configure the dhcp server
#vim /etc/dhcp/dhcpd.conf
default-lease-time 600;
max-lease-time 7200;
allow booting;
allow bootp;
authoritative;
subnet 192.168.0.0 netmask 255.255.255.0 {
range 192.168.0.1 192.168.0.11;
next-server 192.168.0.254;          <= tftp Server ip
filename "pxelinux.0";
}
:wq

#chkconfig dhcpd on;/etc/init.d/dhcpd restart

3. Configure tftp server
#vim /etc/xinetd.d/tftp
disabled = no
:x

Mount RHEL6 OS dvd on /media directory & copy files required for tftp server
#mount /dev/scd0 /media

#cp -rv /media/isolinux/* /var/lib/tftpboot

#cp -rv /usr/share/syslinux/pxelinux.0 /var/lib/tftpboot

#mkdir /var/lib/tftpboot/pxelinx.cfg

#cp /var/lib/tftpboot/isolinux.cfg /var/lib/tftpboot/pxelinux.cfg/default

Make the OS dump
#cp -rv /media/* /var/www/html

#vim /var/lib/tftpboot/pxelinux.cfg/default
                                                                  <= Make this entery at bottom
label RHEL6-32.bit
menu label ^Install RHEL6-32.bit Unattended
menu defult
kernel vmlinuz
append initrd=initrd.img linux ks=http://192.168.0.254/ks.cfg
:wq
4. Create a ks file by the name of ks.cg, to make pxe unattended by using system-config-kickstart & save it in /var/www/html

5. Start the service xinetd, httpd & on the tftp server
#chkconfig xinetd on ; /etc/init.d/xinetd restart

#chkconfig tftp on

#chkconfig httpd on ; /etc/init.d/httpd restart

Now pxe is ready to Install single OS.

ssh-keygen Process

[root@test ~]# ssh-keygen
Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa):
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /root/.ssh/id_rsa.
Your public key has been saved in /root/.ssh/id_rsa.pub.
The key fingerprint is:
0d:f3:e2:dc:63:be:c9:dd:d3:0c:6c:16:62:6e:55:0e root@NDC-LVA-ePDSJB
[root@test ~]# cd .ssh/
[root@test .ssh]# lltotal 12
-rw------- 1 root root 1675 Jun  5 11:39 id_rsa
-rw-r--r-- 1 root root  401 Jun  5 11:39 id_rsa.pub
-rw-r--r-- 1 root root 1183 Apr 17 19:09 known_hosts
[root@test .ssh]# ssh-copy-id -i id_rsa.pub  (Remote IP)
root@Remote IP's password:

Now try logging into the machine, with "ssh "Remote IP'", and check in:  .ssh/authorized_keys
to make sure we haven't added extra keys that you weren't expecting.

[root@test.ssh]# ssh Remote IP

Last login: Mon Jun  4 16:18:03 2012 from Local IP

[root@test ~]# cd .ssh/
[root@test .ssh]# lltotal 8
-rw------- 1 root root 401 Jun  5 11:40 authorized_keys
-rw-r--r-- 1 root root 789 Apr  2 16:11 known_hosts