Monday, November 25, 2013

Configuring Network in Centos 6.4 Virtual Box with Screen Shots

This is a guide on configuring network in Centos Virtual Box with screenshots

Requirements

  1. Virtual Box 
  2. Centos 6.3 or 6.4 (I used 6.4 )

Step 1 : Configure Virtual Box Network Settings

There are different modes or ways you can configure Virtual box network settings.
  1. Not Attached
  2. NAT
  3. Bridged Adapter
  4. Internal Network
  5. Host-Only Adapter
  6. Generic Driver
    7. You can find more details about the different modes here.
I will be using the Bridged Adapter mode for this guide. It is faster as it treat the VM as an individual host within the network.
Open Virtual Box and right click on your CentOS VM, and click on “Settings“.
Go to the "Network tab" then changed the "Attached to" field to "Bridged Adapter". Choose "Name" to your network interface. Then click "ok" to save the configuration. Click "Show" to run the machine.
 

Step 2: Configure CentOS network settings

Method 1: Dynamic IP

We can configure the network by using Dynamic IP address which are assigned automatically by the DHCP server. This is the simplest way to configure your network.

NOTE: You will have a line that starts with HWADDR in the your config file, do not change or modify that line. In your terminal, type the following: 
vi /etc/sysconfig/network-scripts/ifcfg-eth0
Now, add/modify the file as follows (DO NOT CHANGE the HWADDR line your config file): 
DEVICE=eth0
HWADDR=08:00:27:36:3F:37
TYPE=Ethernet
UUID=1e4ee4d1-e438-4db2-9cb5-45e7a488be88
ONBOOT=yes
NM_CONTROLLED=yes
BOOTPROTO=dhcp
Now, save the file by pressing “ESC” and typing :wq and hit ENTER.
To view your network config file. type the following in the terminal: 
[root@localhost ~]# cat /etc/sysconfig/network-scripts/ifcfg-eth0
DEVICE=eth0
HWADDR=08:00:27:36:3F:37
TYPE=Ethernet
UUID=1e4ee4d1-e438-4db2-9cb5-45e7a488be88
ONBOOT=yes
NM_CONTROLLED=yes
BOOTPROTO=dhcp
Now, you will have to restart your network. You can do so by typing the following in the terminal: 
service network restart
Your result must be 
[root@localhost ~]# service network restart
Shutting down interface eth0:                              [  OK  ]
Shutting down loopback interface:                          [  OK  ]
Bringing up loopback interface:                            [  OK  ]
Bringing up interface eth0:
Determining IP information for eth0... done.
                                                           [  OK  ]
To view your IP address, type the following in your terminal: 
ifconfig eth0
You can see your IP Address of the interface eth0 next to the field “inet addr:” as shown below:
Now, if you have internet access, then you can check if you are able to ping any website. And you should be able to get the reply. For example, in your terminal type: 
 
ping google.com
 
You can press CTRL+ C to stop the ping command.
So, Hurray! you have successfully setup up your network in your CentOS Virtual Box.

Method 2: Static IP

 We can also assign the network information manually by assigning the IP Address, NETMASK , GATEWAY in the network interface config file.
NOTE: You will have a line that starts with HWADDR in your config file, do not change or modify that line.

Step 1:

 In you terminal, type: 
vi  /etc/sysconfig/network-scripts/ifcfg-eth0
Now, edit/merge the file to the following 
DEVICE=eth0
HWADDR=08:00:27:EB:C1:68
TYPE=Ethernet
UUID=38341514-767c-4546-9154-859a7b495642
ONBOOT=yes
NM_CONTROLLED=no
BOOTPROTO=static
IPADDR=172.16.2.105
GATEWAY=172.16.0.1
Now, press ESC and type :wq and hit ENTER to save and exit the configuration file. 
cat /etc/sysconfig/network-scripts/ifcfg-eth0
 

 Step 2: Change Host name: 

To change host name , you have to edit the config file /etc/sysconfig/network. 
vi /etc/sysconfig/network
Now, you will see a file such as the one shown below:

To change the hostname , you can change the highlighted to any thing you want. Press ‘i‘ or INSERT to edit the file. After making necessary changes, you can save the file by pressing ESC followed by :wq and hit ENTER.
Now, restart to make necessary changes. You can reboot by typing the following in the command line: 
reboot
After reboot, login and check your hostname by typing the following in the terminal / command line : 
hostname
Step 3: Assign DNS Server IP

 To manually assign primary and secondary DNS Server IP addresses, in your terminal type: 
vi /etc/resolv.conf
Now, edit this file to the following: 
; generated by /sbin/dhclient-script
nameserver 8.8.8.8
nameserver 8.8.4.4
Now, press ESC and type :wq and hit ENTER to save and exit the configuration file.
Now, if you want you can make sure you have entered and saved the correct configuration(It is a good practice to double check :D ). To view your dns config file, in your terminal type: 
cat  /etc/resolv.conf

 Step 4: Restart network:

Finally, all you have to do is to restart your network service. To so so, type the following in the terminal: 
 service network restart

[root@centosAshley02 ~]# service network restart
Shutting down interface eth0:                              [  OK  ]
Shutting down loopback interface:                          [  OK  ]
Bringing up loopback interface:                            [  OK  ]
Bringing up interface eth0:                                [  OK  ]
Now, you can check your Current IP configuration, by typing the following in the terminal:
Now, if you have internet access, then you can check if you are able to ping any website. And you should be able to get the reply. For example, In your terminal type: 
ping imbaprogramming.blogspot.com

You can press CTRL+ C to stop the ping command.
So, Hurray! you have successfully setup up your network manually in your CentOS Virtual Box.
 
source : http://extr3metech.wordpress.com/2013/05/23/configuring-network-in-centos-6-3-virtual-box-screenshots/