GNS3 • View topic - basic understanding of connecting gns3 to a real switch..

View unanswered posts | View active topics

Board index » GNS3 » Installation » Installation on Windows

All times are UTC

basic understanding of connecting gns3 to a real switch..

Page 1 of 1

[ 5 posts ]

Print view

Previous topic | Next topic

Author

Message

chanochm

Post subject: basic understanding of connecting gns3 to a real switch..

Posted: Fri Aug 19, 2011 2:55 pm

Joined: Fri Aug 19, 2011 2:48 pm
Posts: 2

i know its probably around here some where, but i wasn't able to find it.
is there a way to bind a physical NIC to a interface of a gns router and then connect the nic to a real switch?
i know there's a way to do it, but is it a way that i don't need to put any IP address on the NIC itself? all i want is a clean connection between the router and the switch.
if any1 can direct me to a tutorial or explain himself ill be grateful.

i tried to connect the gns3 router to a cloud that has ethernet nio with the physical interface, and the interface of the router did came up. but still didnt see anything in the cdp neighbors nor can i ping the router from a pc connected to the switch.

thanks in advance.

Top

rednectar

Post subject: Re: basic understanding of connecting gns3 to a real switch..

Posted: Fri Aug 19, 2011 8:42 pm

Joined: Fri Mar 05, 2010 11:33 am
Posts: 801
Location: Australia

This is fairly easy to do - you simply add a cloud to your topology, and configure the cloud to bind to your computer's physical interface. AFTER you have configured the cloud, you con connect it to say fa0/0 of your router.

So:
1. Create a topology with a router and a cloud
2. Right-click on the cloud, select Configure
3. In the left hand pane, click on the cloud C1
3. Select the [NIO Ethernet] tab
4. From the GEneric Ethernet NIO (Administrator access required) drop down list, select the adapter you want to link to. The name of this adapter should appear in the box below it.
5. **** Important *** Click [Add]
6. Click OK

Attachment:

add NIO adapter.jpg [ 58.8 KiB | Viewed 4088 times ]

You should now be able to connect the cloud to your router and if say you have a DHCP server on your network, it will even pick up an IP address. See session below:

Code:

Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
Connected to Dynamips VM "R1" (ID 0, type c3725) - Console port


R1#
R1#sh ip int br
Interface                  IP-Address      OK? Method Status                Protocol
FastEthernet0/0            unassigned      YES unset  administratively down down    
FastEthernet0/1            unassigned      YES unset  administratively down down    
R1#conf t
Enter configuration commands, one per line.  End with CNTL/Z.
R1(config)#int f0/0
R1(config-if)#no shut
R1(config-if)#ip address dhcp 
*Mar  1 00:01:20.047: %LINK-3-UPDOWN: Interface FastEthernet0/0, changed state to up
*Mar  1 00:01:21.047: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to up
R1(config-if)#end
*Mar  1 00:01:25.359: %SYS-5-CONFIG_I: Configured from console by console
R1#sh ip int br
Interface                  IP-Address      OK? Method Status                Protocol
FastEthernet0/0            unassigned      YES DHCP   up                    up      
FastEthernet0/1            unassigned      YES unset  administratively down down    
R1#
*Mar  1 00:01:33.263: %DHCP-6-ADDRESS_ASSIGN: Interface FastEthernet0/0 assigned DHCP address 192.168.1.158, mask 255.255.255.0, hostname R1

R1#sh ip int br
Interface                  IP-Address      OK? Method Status                Protocol
FastEthernet0/0            192.168.1.158   YES DHCP   up                    up      
FastEthernet0/1            unassigned      YES unset  administratively down down    

I did my example on a Macintosh then repeated it on Linux and Windows 7 (64bit) all running on the same network (in fact, the Windows 7 and Linux are VMs on my Macintosh) and they could all ping each other. (Although the Windows instance was a lot more sluggish than the other two)

Attachment:

add NIO adapter.jpg [ 58.8 KiB | Viewed 4088 times ]

Attachments:

add NIO adapter2.png [ 37.09 KiB | Viewed 4089 times ]

_________________
RedNectar
http://rednectar.net
@rednectarchris
GNS3 WorkBench-a VMware image of Ubuntu with GNS3 and VPCS installed and a collection of exercises/labs

Top

rednectar

Post subject: Re: basic understanding of connecting gns3 to a real switch..

Posted: Sat Aug 20, 2011 10:39 am

Joined: Fri Mar 05, 2010 11:33 am
Posts: 801
Location: Australia

I also just came across this - don't know if it is any good, but fwiw http://www.youtube.com/watch?v=wC-n8Jy8 ... re=related

_________________
RedNectar
http://rednectar.net
@rednectarchris
GNS3 WorkBench-a VMware image of Ubuntu with GNS3 and VPCS installed and a collection of exercises/labs

Top

chanochm

Post subject: Re: basic understanding of connecting gns3 to a real switch..

Posted: Sat Aug 20, 2011 9:18 pm

Joined: Fri Aug 19, 2011 2:48 pm
Posts: 2

Thanks alot for your answer!
i actually did what you explained and it didnt work first but then i figured out i have a problem in the switch configuration.
one more interesting thing is that when i do a show cdp neighbors on the switch i can see that router but when i do cdp neighbors on the router i cant see the switch (tough the ping is working flawlessly) i wonder why its happening.
maybe the NIC on the computer dont know what the cdp frame is and just throw it?

Top

rednectar

Post subject: Re: basic understanding of connecting gns3 to a real switch..

Posted: Sat Aug 20, 2011 9:23 pm

Joined: Fri Mar 05, 2010 11:33 am
Posts: 801
Location: Australia

I have to admit there have been times when I've seen strange things like that happen when connecting to a "real" network - one way pings and one way ARPs as well. Sometimes putting a generic switch between your PC and the router helps, sometimes not.

As you say though, run a wireshark capture to debug.

_________________
RedNectar
http://rednectar.net
@rednectarchris
GNS3 WorkBench-a VMware image of Ubuntu with GNS3 and VPCS installed and a collection of exercises/labs

Top

Page 1 of 1

[ 5 posts ]

Board index » GNS3 » Installation » Installation on Windows

All times are UTC

Who is online

Users browsing this forum: No registered users and 1 guest

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum