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802.1q trunks to NICs to support multiple VLANs?

I'm trying to find out how it works to connect trunks to our servers (NICs) but I still can't get it to work. What am I missing?

What we simply want to do is to connect our Windows 2000 Server installed on a DL380G3 (with NC7781 NIC) to a port on our Cisco 2950 switch, which only support 802.1q. The port is configured with the command:

"switchport mode trunk"

No VLANs are cleared from the trunk.

What we want to do is have the NIC to be configured to be on both:

VLAN10 ( and

VLAN20 (

What else do you have to do except configuring the IP-adresses for the NIC? Can't find any settings ni the driver. We have also tried teaming the NICs and connecting the NICs to seperate switches and configuring them as trunks.

Community Member

Re: 802.1q trunks to NICs to support multiple VLANs?

Depends on the NIC. Are you sure the one you have even supports it? It sounds like you're using a Compaq server, so one would assume it's a Compaq NIC. That being the case, ask Compaq. :)

BTW, here's an example of a NIC that supports is:

Community Member

Re: 802.1q trunks to NICs to support multiple VLANs?

It's the builtin on a ProLiant DL380G3 with the NC7781 network card. It's actually some kind of Intel-NIC, Intel Pro 1000 we think. Problem is that HP support has problems finding the info for me but when I talked to some technicians on our local HP office they told me YES - no problem.

Also if you look for the NIC drivers for DL380G3 there's a "hp Tested and Approved Linux 802.1q VLAN Driver" on theit homepage but that's only for Linux so apparantly the NIC does support 802.1q. But maybe the Win2000-driver doesn't support that?

I just want to make sure I've done the Cisco configuration correctly and how you "usually" configure the NIC? Is there usually something you have to configure on the NIC or do you usually just "enable" 802.1q support on the NIC?

Community Member

Re: 802.1q trunks to NICs to support multiple VLANs?

Yes, you will have to make sure you have a NIC that has 802.1q VLAN tagging support in the WIndows driver.

You won't find that with your average NIC. I have this working in Windows 2000 with an Intel PRO/100 NIC. The Intel PROSet software allows you to create the VLANS, and associate them with the correct VLAN ID's.

Then when the configuration is applied, your original physical ethernet interface is disabled, and new 'virtual' local area network connections appear (as many as you configured), where you can configure them as if they were independant physical NICs, each with their own IP addresses, protocols, etc.

Community Member

Re: 802.1q trunks to NICs to support multiple VLANs?

Ah! That's exactly what I'm looking for. The hard thing now is to find out what the integrated NIC in the Proliant DL380G3 is. It's a NC7781 but really it's some kind of Intel card. The support of HP told me that it didn't support 802.1Q, but then thy came back to me to try the Intel PRO/1000 NIC card drive since it was actually the same card.

But then another technician came back to me and told me that they supported 802.1Q.

Why we want to do this is because we want to use two seperate IP-adresses - one for production and one for backup. The PHYSICAL NICs should be connected to different switches and using STP (or?) we want to make sure that all traffic for Production IP using one switch/NIC and all traffic for Backup IP should use the other one - but still they are redundant for eachother if one switch fails. Does this sound like something that can be done?

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