Ask Your Question

Realtek PCIe GBE Family Controller - VLAN Tag

asked 2022-01-26 09:46:37 +0000

Nullblicker gravatar image

Hello all,

We use the Realtek PCIe GBE Family Controller network adaptor (RTL8168) in our Engineering Station to connect the Engineering Station with our PROFINET-Network. In the PROFINET we use SIEMENS Scalance Switches and use VLAN-Tagging. We have mirrored a Switch-Port and sniffer with the Engineering Station and Wireshark. We see the Network Traffic correctly. But we want also see the VLAN-Tag with ID 0 and Priority 6 (PROFINET-Standard). When we connect the Mirror-Port with a Laptop with Intel Network Card, we see the VLAN-Tag correctly (adjusting registry settings before, MonitorModeEnabled = 1, MonitorMode = 1).

So the Realtek Card is the problem.

There is an advise in another topic here for Realtek network card, which say, that we have to adjust the registry:

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

We have done it, we see now VLAN-Tags also with the Realtek, but no more network communication from this card is possible. It seems, there is only a mirror/monitor function available.

In the windows device manager is for the realtek card the property "priority and vlan" enabled. Also disabling brings no improvement.

Is there another way?

Thank you for your help.

edit retag flag offensive close merge delete


This doesn't seem to be a Wireshark question, more one for a Windows or RealTek forum.

grahamb gravatar imagegrahamb ( 2022-01-26 11:14:25 +0000 )edit

1 Answer

Sort by ยป oldest newest most voted

answered 2022-01-27 06:18:02 +0000

Jaap gravatar image

This is actually perfect. You said that the setup was to connect the Realtek card to the mirror port of a switch. You don't want to be communicating via a port that's a mirror port, you only want to monitor. No risk of confusing the switch, nor the OS on the Engineering Station by mix of traffic. Also no contention on the mirror port.

What you do is stick another NIC in the Engineering Station and use that for the actual network traffic and keep this for monitoring only.

edit flag offensive delete link more


Hallo and thank you for your answers.

We had deactivated the mirror port on the switch, when we had tested the VLAN functionallity on the Engineering Station (adjusting the registry parameters of the realtek card). So no mirroring wars active on the switch but no active network traffic from the Engineering Station to the network was possible. When we had deactivated the VLAN functionallity of the Realtek card (original registry parameters), network traffic was possible. So it seems, that the registry parameters "MonitorModeEnabled = 1" leads to an only monitor functionallity of the Realtek card.

See you

Nullblicker gravatar imageNullblicker ( 2022-01-27 07:14:41 +0000 )edit

Your Answer

Please start posting anonymously - your entry will be published after you log in or create a new account.

Add Answer

Question Tools



Asked: 2022-01-26 09:46:37 +0000

Seen: 634 times

Last updated: Jan 27