I have been having a lot of trouble getting GNS3 to talk to a real network lately.
I have been doing relatively simple setups. I am not sure what has changed.

(3725) R4 - fa1/15 802.1q ====== PC NIC (CLOUD) ====== fa0/3 802.1q SW3 (3550EMI)

int vlan 120 10.0.12.4/24-------------TRUNK---------------int vlan 120 10.0.12.3/24

I have tried using my realtek onboard NIC's and my Intel PCI-X 1000Pro Dual port server adapter.

I am getting strange things with CDP. Here is on the REAL 3550:



And then here is the virtual 3725:



Can't ping across.

I am on Windows 8. I set this SAME thing up on my Mint laptop and it works flawlessly. Is there anything with Windows 8 that could be causing the problem or what am I missing?

Regards,

xtropx

What I have tried:

Reloading the router in GNS3 after configuring it.
Checking the config on each of the routers. (Ensuring they are /24 and in 10.0.12.x, ensuring they are dot1q trunks, enabled, and speed 100/duplex full)
Moving between the pci-x nics and the realtek nics on my main board.
Disabling unused nics.
Running GNS3 as administrator
Running GNS3 in compatibility mode for Windows 7
Checking to see if priority and vlan are enabled in configuration of nic settings. They are.
Re-installing winpcap
http://www.intel.com/support/network/sb/CS-005897.htm
Disabling ZoneAlarm firewall, and windows firewall
Uninstalling ZoneAlarm firewall completely, and turning off windows firewall
Using older versions of GNS3

There are issues with Windows stripping the vlan tags.
- What is your NIC MTU set to?
- If you run Wireshark on the physical interface can you see the VLAN tags arriving from the 3550?

_________________
GNS3 0.8.4 running on Windows 8.1
GNS3 0.8.4 running on CentOS 6.5

Hello nickbeee thanks for the reply. After spending most of the day on it yesterday I decided to use wubi and copy my IOS images over.

Works PERFECT in ubuntu, same network interfaces. So I can confirm this is a windows issue.
I believe I did set the MTU for at least 1 of the network interfaces in windows a bit higher before, but I can't quite remember.

I think I have it working here now, W8.1 with a real 3550. Set MTU for > 1500 mine has option for Jumbo and I set 2k.


Then I found it was necessary to run GNS3 with administrator privs. I also have WinPcap installed in W7 compatibility mode.

EtherSwitch 3725 -


And then 3550 -


I'll try some vlans across the trunk later when I have more time to see if the VLAN tag stripping issue is there... HTH.

_________________
GNS3 0.8.4 running on Windows 8.1
GNS3 0.8.4 running on CentOS 6.5

Examining the interface with Wireshark, I tried to ping a SVI I created in the vlan on the 3550. I can see 802.1Q tagged packets going out with ARP boradcasts, but the ARP replies from the switch have the 802.1Q tags stripped.

I then dicovered there is a Realtek utility for creating/managing VLANS on Windows so I downloaded and installed this - It's the Windows Diagnostic Program here. After installing it I see some extra drivers appear on the NIC and there is a nice configuration tool to add extra tagged vlans which appear as additional network interfaces. I can ping with a tagged vlan using one of these but I still can't get it to work with GNS3 using the native vlan interface.

I've followed suggestions to disable vlan tagging and priority on the native interface but no success yet. I'll have another go at re-installing WinPcap in case anything has changed.

Now if you want to break out a handful of virtual machines from your PC to a switch over a .1Q trunk then this utility is perfect... Unless you have time to burn I'd go with Linux ;-)

_________________
GNS3 0.8.4 running on Windows 8.1
GNS3 0.8.4 running on CentOS 6.5

nickbeee

Thanks for taking the time to lab this out. I really appreciate it.
I have also increased the MTU and installed winpcap again using win7 compatibility settings.
I haven't had much luck either. I have also found the drivers for my Intel NIC's are from 2009, and there are no Win 8 drivers available (just WIN7_PROx64)
One could consider us having some success, however, as we have indeed identified the problem to be Windows 8.

This is rather unfortunate as my plan was to build a MPLS L3VPN cloud in GNS3 to use as the WAN connection for my voice lab (VLAN from each "PE" to my 2811's), and still be able to bind NIC's to CIPC (save $$$ on IP Phones) Always something right? =\

I might try just going back to windows 7 and seeing if that corrects the problem, or just run GNS3 on my mint laptop for now.

Again, thanks for the help. :)

I am on Windows 8. I set this SAME thing up on my Mint laptop and it works flawlessly. Is there anything with Windows 8 that could be causing the problem or what am I missing?

_________________
GuL

I finally got my Realtek PCIe GBE Controller to do router on a stick with Windows 8.1 / Server 2012 R2!

Here's how:

1. I updated my drivers to the latest: http://www.realtek.com.tw/downloads/dow ... Down=false

2. Once installed, went to my regedit in: HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class\{4D36E972-E325-11CE-BFC1-08002BE10318}\00nn
Where nn is the physical instance of the network port where you want to capture the VLAN tags.

3. Added / Edited the following DWORDS:

MonitorModeEnabled - 1
MonitorMode - 1
*PriorityVLANTag - 0
SkDisableVlanStrip - 1

4. Restarted my machine, and voila! Working router on a switch! No need to use Linux!