Adding VirtualBox Guest to GNS3

Adding VirtualBox Guest to GNS3

1. Install GNS3 and VirtualBox

2. Add a 'Host-only Network' to VirtualBox Manager
File>Preferences>Network
Click the 'Add host only network' button (right side)
A 'vboxnet0' network appears in the list

3. Add a guest OS to VirtualBox

4. Add guestOS to host-only network
Right the newly added guestOS inthe VBox manager
Settings>Networks>Adapter1
Check 'Enable Network Adapter'
Select 'Host-only adapter' in 'Attached To:'
Select 'vboxnet0' in 'Name:'
Under 'Advanced' section uncheck 'Cable connected'
Note down the MAC address

5. Selecting VBoxwrapper in GNS3
GNS3 : Edit>Preferences>VirtualBox>General Settings>Path to VBoxwrapper
Locate the 'vboxwrapper.py' in the 'vboxwrapper/'
Click 'Test Settings'
If 'VBoxwrapper and VirtualBox API 4.1.2_Ubuntu have been successfully started' then its OK

6. Selecting the guestOS in GNS3
GNS3 : Edit>Preferences>VirtualBox>VirtualBox Guest
Click 'Refresh VM List'
From the 'VM List', select the guestOS and give it an 'Identifier name'
Click 'Save' , the Id Name appears in the list below 'Save'
Click 'Apply' and 'OK'

7. Adding VirtualBox guest to GNS3
Drag and drop 'VirtualBox guest' to the central panel

8. Adding Router to GNS3 and Setup an interface 
Drag and drop a Router from the left panel to the central panel
(Note: You should have loaded the particular Routers IOS image in GNS3
              See 'GNS3 non superuser setup' on how to add IOS images
)

9. Connecting Router and guestOS
Click 'Add a Link' and Select 'Ethernet'
In the central Panel, Left Click the Router and then guestOS (select an adapter if asked)
Click the '(X)' to stop adding links
A link appears between the guestOS and Router (in the central panel)
Red dots appear at both the ends of the links

10. Configuring the router 
Right and click 'Start' on the Router in the central panel
Red dot near the Router turns green
Right and click 'Console' the Router in the central panel
In the terminal window that appear
Wait for it to boot (press Enter when asked to get started)
( This not the best way to learn to configure a router.Refer some Cisco or CCNA materials.
     I learned it from CCNA book by Todd Lammle.
)

R3#configure terminal
R3(config)#interface ethernet 0/0
R3(config-if)#ip address 192.168.1.1 255.255.255.0
R3(config-if)#no shutdown
R3(config-if)# [[Ctrl+C]]
R3#copy running-config startup-config
[Enter]
[Enter]
R3#Exit

Close the terminal window

11. Configuring guestOS
Right and click 'Start' on the guestOS in the central panel
Red dot near the guestOS turns green
After booting, Login and start a terminal

guestOS# ifconfig -a
 from the list that appears find the ethernet number (eg : eth3) of the adapter whose 
 HWaddr is same as the MAC address we noted down in step 4.
guestOS# ifconfig eth3 192.168.1.2 up
 'eth3' is the adapter in my case, can be different in yours
guestOS# ping 192.168.1.1

if ping worked then SUCCESS
(Note : while building larger networks add default gateway as 192.168.1.1 to the guestOS's adapter)

12. Save the topology setup.