Redhat Enterprise Linux 6 Security Guide Free Download
Because of the increased reliance on powerful, networked computers to help run businesses andkeep track of our personal information, entire industries have been formed around the practice of
network and computer security. Enterprises have solicited the knowledge and skills of security experts
to properly audit systems and tailor solutions to fit the operating requirements of their organization.
Because most organizations are increasingly dynamic in nature, their workers are accessing critical
company IT resources locally and remotely, hence the need for secure computing environments has
become more pronounced.
Unfortunately, many organizations (as well as individual users) regard security as more of an
afterthought, a process that is overlooked in favor of increased power, productivity, convenience, ease
of use, and budgetary concerns. Proper security implementation is often enacted postmortem — after
an unauthorized intrusion has already occurred. Taking the correct measures prior to connecting a
site to an untrusted network, such as the Internet, is an effective means of thwarting many attempts at
intrusion.
Note
This document makes several references to files in the /lib directory. When using 64-bit
PXE Server in RHEL 6 ?
How to configure PXE Server in RHEL 6 ?
Server IP settings.
IP 192.168.0.70 SUBNET 255.255.255.0 nmcontrolled no onboot yes DNS1=192.168.0.1
Yum install system-config-kickstart # Install the kickstart package. system-config-kickstart # run the kickstart utility.
In the second last option you can remove text mode installation option and opt For a graphical one.
Select the http installation method
Use the defaults.
In the disk label option choose the first option (Initialize the disk label). The partitions that I have created are like this. Mount Point type size /boot ext4 500 swap swap 2048 / ext4 18000
Make sure that SELinux option is disabled and Security level is set to Disable firewall.
Save the ks.cfg file to the filesystem.
Yum install –y syslinux xinetd tftp-server dhcp httpd # Install all the required packages through yum mkdir /var/lib/tftpboot/pxelinux.cfg cp /usr/share/syslinux/pxelinux.0 /var/lib/tftpboot/ vi /etc/xinetd.d/tftp # Open the xinetd settings to enable tftp server. # at line 14 set the parameter to no from yes. Disable=no
service xinetd restart
# Restart the service to apply the settings made.
chkconfig xinetd on
# set the service to start with each subsequent system reboots.
vi /etc/dhcp/dhcpd.conf
# Open the file and configure the DHCP Server.
# Global Options
Allow booting;
Allow bootp;
authoritative;
# Subnet definition
subnet 192.168.0.0 netmask 255.255.255.0 {
# Parameters for the local subnet
option routers 192.168.0.1;
option subnet-mask 255.255.255.0;
option domain-name “example.com”;
option domain-name-servers 192.168.0.1;
default-lease-time 21600;
max-lease-time 43200;
# Client IP range
range dynamic-bootp 192.168.0.100 192.168.0.200;
filename “pxelinux.0”;
next-server 192.168.0.70;
}
# Here the next–sever parameter is the address of the kickstart server.
service dhcpd restart
Chkconfig dhcpd on
# restart the service and make it permanent.
mkdir –p /var/pxe/rhel6
mkdir /var/lib/tftpboot/rhel6
# make some required directories.
Insert your RHEL 6 dvd
mount /dev/cdrom /mnt
# Mount it to /mnt
ls –l /mnt
# Check the contents to see if it is properly mounted.
cp –ivr /mnt/* /var/pxe/rhel6
# copy all the contents to the /var/pxe/rhel6 directory.
umount /mnt
eject
# after the file copy operation unmount and eject the dvd.
cp /var/pxe/rhel6/images/pxeboot/vmlinuz /var/lib/tftpboot/rhel6
cp /var/pxe/rhel6/images/pxeboot/initrd.img /var/lib/tftpboot/rhel6
# copy the vmlinuz and initrd.img files to the tftpboot directory.
cp /usr/share/syslinux/menu.c32 /var/lib/tftpboot/
# copy the menu file.
vi /var/lib/tftpboot/pxelinux.cfg/default
timeout 100
default menu.c32
menu title $$$$$$Boot Menu$$$$$$
label 1
menu label ^ 1) RHEL6
kernel rhel6/vmlinuz
append initrd=rhel6/initrd.img ks=http://192.168.0.70/ks/ks.cfg ksdevice=eth0
# Prepare the boot menu.
chkconfig httpd on vi /etc/httpd/conf.d/pxeboot.conf # create new entry Alias /rhel6 /var/pxe/rhel6 Options Indexes FollowSymLinks Order Deny,Allow Deny from all Allow from 127.0.0.1 192.168.0.0/24 # Ip address you allow service httpd restart (ignore the domain name error if it occurs.) # Prepare the httpd server mkdir /var/www/html/ks cp /ks.cfg /var/www/html/ks/ks.cfg chmod 644 /var/www/html/ks/ks.cfg # make the directory and copy the kickstart file to it. # and make the kickstart file globally read only.
The pxe server is ready. Plug a computer into the network and boot it through LAN using pxe. The client pc should have a display as below.
