SLES 11 - Complete PXE Server configuration to install SuSE Liunx Enterprise Server 11

Hello Friends, 

Its been long time i did not put any contents in my blog. I was doing research in some interesting stuffs in linux and also busy with work. This time i am coming up with SuSE Linux Enterprise Server 11 not with Redhat. ! 
Let us discuss about how do we configure PXE server to install SuSE Linux Enterprise server OS into Clients. Similar post on RHEL 7 can be found on the following link : Complete Guide for PXE Server configuration in RHEL 7.0

Breaking down the task to configure PXE Server, Here is the list :

1. DHCP server  ( To provide IP address to client )
2. Apache2 Server configuration ( To transfer the DVD image to Client for OS installation)
3. TFTP server configuration ( To Transfer the PXE kernel and other supporting files to Client System )
Check the version of SUSE Linux using the following command.







Let us configure DHCP Server first. for that we need to install the dhcp-server package into server.
I am using Zypper to install dhcp server pakage. or else you could run #yast dhcp-server to install and configure dhcp server.

# zypper in dhcp-server

Now configure dhcp server. edit the /etc/dhcpd.conf and update the following entries.
(Move original /etc/dhcpd.conf file to some other name and create new dhcpd.conf with the following entries.)
Here IP range is from 192.168.1.10 to 192.168.1.20

default-lease-time 14400;
ddns-update-style none;
subnet 192.168.1.0 netmask 255.255.255.0 {
  range dynamic-bootp 192.168.1.10 192.168.1.20;
  default-lease-time 14400;
  max-lease-time 172800;
  next-server 192.168.1.3;
  filename "pxelinux.0";
}

update the /etc/sysconfig/dhcpd file with the following entries.
DHCPD_INTERFACE="eth0"

Restart the dhcpd service and enable it on start-up using the following command.
# rcdhcpd restart
#chkconfig --level 35 dhcpd on











Step1 is finished. Now lets configure http to share the DVD image.install the apache2 package using the following command.

# zypper in apache2

Mount the SuSE Linux DVD into /srv/www/suse-os/dvd directory.
#mkdir -p /srv/www/suse-os/dvd
#mount /dev/sr0 /srv/www/suse-os/dvd

DVD is mounted, make the mount point persistent across reboot. add the following entry in /etc/fstab
/dev/sr0             /srv/www/suse-os/dvd       iso9660 defaults        0 0

I am going to configure a virtual host in apache to provide the DVD image.
create a file named suse-os.conf under /etc/apache2/vhosts.d/ and add the following lines into suse-os.conf file.

<VirtualHost *:80>
    ServerAdmin vinil@vinizlinux.com
    ServerName pxe-suse.vinizlinux.com
    DocumentRoot /srv/www/suse-os
    <Directory "/srv/www/suse-os">
       Options Indexes FollowSymLinks
       AllowOverride None
       Order allow,deny
       Allow from all
    </Directory>

</VirtualHost>

Start the apache using #rcapache2 start


And enable the apache in startup using #chkconfig --level 35 apache2 on  and then check the apache in a web browser.

Now the final part  let us work on tftp part.
for configuring tftp we need to install the tftp package also we need the syslinux package which contains the pxelinux kernel to boot the client from PXE server.
Run the following command to install tftp and syslinux package.
# zypper in tftp syslinux


Edit the tftp configuration file /etc/xinetd.d/tftp and change the following line to "no".
 disable                 = no

create the tftpboot directory under / and create the pxelinux.cfg directory under /tftpboot

now copy the pxelinux.0 file to /tftpboot.
# cp /usr/share/syslinux/pxelinux.0 /tftpboot/
We need to copy some more supporting files for PXE boot for that we need to mount the SuSE OS DVD.
#mkdir -p /srv/www/suse-os/dvd

# mount  /dev/sr0 /srv/www/suse-os/dvd

This same mount point can be used in Apache for giving the OS image to PXE clients. cd to /srv/www/suse-os/dvd/boot/x86_64/loader/ directory where we have the kernel , initrd, boot tests etc.
# cd /srv/www/suse-os/dvd/boot/x86_64/loader/
# cp linux initrd bootlogo memtest message biostest /tftpboot/

Copy the isolinux.cfg file to /tftpboot/pxelinux.cfg/ as default
# cp isolinux.cfg /tftpboot/pxelinux.cfg/default

Now edit the default file and provide the installation source and method of installation. here i am using ssh based suse installation. you could use vnc or ssh to do installation. Entries in the default file is shown below.

Now restart the xinetd services using the following command. and enable it on startup.
# rcxinetd start
#chkconfig --level 35 xinetd on

This installation is not fully automatic we need to give some inputs to complete the installation. for the automated installation we need to configure autoyast. i will put a new post on it later.
Now lets boot the client and check whether its able to boot or not. 
Yes !! Yes!! its able to boot from PXE Server



Now type linux on the prompt it will start installation.
After sometime you will see the following screen to start installation. you need to connect this client from anywhere using ssh to provide inputs for finishing the installation.

Here we are using ssh -X , and  X is for X11/X.org forwarding. 
Let us connect the client and check the installation.

Now run yast on prompt it will open a GUI interface to start installation.
Follow the on-screen options and finish the installation.

That’s all! I will be coming up with few more interesting articles on Linux, till then stay tuned to Learn linux and don’t forget to add your valuable comments

DHCP Server configuration in RHEL 7.0

Dynamic Host Configuration Protocol (DHCP) As the name suggests, DHCP is used to control the network configuration of a host through a remote server. DHCP is an excellent alternative to the time-consuming manual configuration of network settings on a host or a network device.
It automatically assigns IP addresses and other network configuration information to systems on a network.

The following Diagram showing the DHCP Operation.



Let us check how to configure DHCP server in Redhat Enterprise Linux 7.0.
First we need to setup a static IP address for the DHCP Server. Use nmcli or edit the configuration file. click here to know how to configure ip address using nmcli.
 
We need to install the DHCP Package using YUM or RPM. For more information on YUM configuration please chick here.
Run # yum install dhcp -y to install dhcp package .

Let us check what all configuration files created after the dhcp package installation. run
# rpm -qlc dhcp command.

Installing the dhcp package creates a file, /etc/dhcp/dhcpd.conf, which is merely an empty configuration file. This is configuration file for IPv4 DHCP .

Looking into this file we could see that there is sample configuration file available for reference.
If do a cat on /usr/share/doc/dhcp-4.2.5/dhcpd.conf.example you would get a better idea to configure DHCP server. there are lot of sample configurations available.

The first step in configuring a DHCP server is to create the configuration file that stores the network information for the clients. Use this file to declare options for client systems.

Here is my DHCP server configuration. my IP address range is 192.168.1.101 to 192.168.1.111. and additionally we are give some options like netmask, router, domain, DNS etc.
subnet 192.168.1.0 netmask 255.255.255.0 {
  range 192.168.1.101 192.168.1.111;
  option domain-name-servers 192.168.1.200;
  option domain-search "vinzlinux.com";
  option subnet-mask 255.255.255.0;
  option routers 192.168.1.100;
  default-lease-time 600;
  max-lease-time 7200;
}


Thats all about DHCP Configuration. There are many options available in DHCP configuration could you refer the man pages and example file for more information. lets restart the DHCP service and enable service.
# systemctl restart dhcpd
# systemctl status  dhcpd
# systemctl enable dhcpd




Now we need to work on client side. Check any ip address is configured in the client.  run #ip add show command.

There  no IP address is configured for eno16777736 interface now.
run #dhclient eno16777736 or take a reboot or restart NetworkManager this will get the ip address from the DHCP server.


You could see the following entries in the /var/log/messages in the DHCP server.

Fore IP lease information you could see in /var/lib/dhcpd/dhcpd.leases file in DHCP server.
You could see something similar to this.


That's all about DHCP server configuration ..! Hope you found this article useful.