Comments on: How to connect GNS3 to the internet in MacOSX

By: Johan Havermans

Johan Havermans — Wed, 26 Oct 2011 11:18:30 +0000

Charles,

I did spend quite some time in getting GNS3 to work on Lion with Virtual Machines such as Parallels Desktop and VirtualBox.
The tuntap stuff gave me headache and also connecting my virtual network to the internet. It is working right now and I documented what I did.

Maybe this post can help you:
http://forum.gns3.net/topic4206.html?sid=6ebdb861bfceebd5c94e96a525167768

For connecting your virtual network to the internet, look at script 3 in section “Step 9: tap0 up – Connecting the virtualized network to your LAN” op page 16.

Good luck

By: Charles

Charles — Sat, 24 Sep 2011 10:58:40 +0000

Hi guys,

After a lot troubleshooting i managed to partially make it work. Problem is that when i issue the

sudo sysctl -w net.inet.ip.forwarding=1

command i get the message:

net: class is not implemented

I am running the Lion OSX and i have no idea how to proceed. Any recommendations?

By: Usersati

Usersati — Tue, 30 Aug 2011 14:37:35 +0000

You are a Freaking genius thanks a lot, i had months looking for these two commands!

a billion of time thanks!

By: James Powis

James Powis — Sun, 22 May 2011 23:01:48 +0000

For those that are having issues with 206 errors:

chmod 666 /dev/tap*
chmod 666 /dev/tun*

By: Sean Cavanaugh

Sean Cavanaugh — Tue, 05 Apr 2011 15:11:01 +0000

I got this to come up… but I can ping from my computer to the virtual router, but not vice versa, firewall is turned off… has anyone else had this problem?

By: Matthew X. Economou

Matthew X. Economou — Mon, 13 Dec 2010 03:46:46 +0000

Those of you encountering 206 errors most likely made a mistake when specifying the TAP device. GNS3 only makes it more confusing, because when you create a generic Ethernet NIO, you can just specify the bare device name (e.g., “en0″), but when you create a TAP NIO, you must specify the full path to the TAP character device (e.g., “/dev/tap0″). In the configs posted above, people have made exactly this mistake – either the full path is omitted entirely (e.g., “tap0″) or it is entered incorrectly (e.g., “dev/tap0″ – note the missing leading “/”).

What I’d like to know, is how to bridge to the TAP interface from VMware Fusion. VMware Fusion will only allow me to bridge to the Ethernet (en0) and AirPort (en1) interfaces from the GUI, and I don’t know how to use any of the command line support tools installed alongside Fusion.

Best wishes,
Matthew

By: Wilson

Wilson — Mon, 15 Nov 2010 01:06:14 +0000

Forgot to put .net conf, here it is:

autostart = False
[127.0.0.1:7200]
workingdir = /Users/”usr”/Documents/GNS3/Projectos/SvM/Lab7/Lab7_working
udp = 10000
[[2621]]
image = /Applications/Dynagen/IOS/c2600-advipservicesk9-mz.124-19.bin
ram = 128
idlepc = 0x81fa91bc
sparsemem = True
ghostios = True
chassis = 2621
[[ROUTER R1]]
model = 2621
console = 2000
x = -107.0
y = -58.0
f0/0 = NIO_tap:dev/tap0
[GNS3-DATA]
configs = Lab7_configs
workdir = Lab7_working
[[Cloud C1]]
x = -360.5
y = -69.0
connections = R1:f0/0:NIO_tap:/dev/tap0

By: Wilson

Wilson — Mon, 15 Nov 2010 01:04:45 +0000

Hey, great post, pitty i havent got it to work yet, i’ve been over these, times after times i dont know what i am doing wrong…. =/
So, what i did is i installed GNS3 and dynamips(installed dynagen and am using dynamips from /Application/Dynagen/) i had some troubles at beggining with dynamips, because it wasn’t inside GNS3 .dmg, dont know why, but now, i have it working alright, i have everything set up, and working, i installed tuntaposx correctly and i can see the tap0-15 tun0-15 when i ls /dev, so all seems ok, but when i try to open the .net with the confs you have it gives this error on dynamips:

netio_tap_create: unable to open TAP device dev/tap0 (No such file or directory)

in gns3:
206-unable to create TAO NIO

i am running dynamips and gns3 has root user, i dont know what else to do, but i think i will try to uninstall all and reinstall if i dont get any solution in next 2 days, cause i have alot to work on and i cant… =/ Ty all for atention. []

By: Joe

Joe — Sun, 07 Nov 2010 19:25:56 +0000

Awesome posts, i’ve been looking for ways to run dynamips/gns3 on my mac.

By: naner

naner — Tue, 26 Oct 2010 03:47:05 +0000

hi, if we successfully configure the router (i.e. Router1) to connect to the internet in GNS3, then we have another router connected to Router1, can NAT work to give the other router an internet connection as well? Thanks!