VLAN aware Network Cards

[SoyGalesa]

Ok, excuse me if this is in the wrong forum but...some questions.

1) What are the practicalities of using a VLAN aware network card. From what I understand they connect to a switch trunk port and carry all VLAN's so that the server sits on all VLAN's simultaneously. Does this mean that I have to assign an IP address for every VLAN that is trunked to the Network Card; or is it enough for the network card to be connected to a trunk port on a switch (dot1q or isl) and it works it out for itself.

2) Anyone recommend a good VLAN aware network card - it must support dot1q trunking and be Netware compliant.

3) Is the OS important or will it work under NT and Netware

Thanks

 

[Degg]

I believe Intel makes NIC's that are VLAN aware. One advantage of this is that you could have one server on all VLAN's to be a DHCP server. I'm not sure the details of IP's, as I havent played with one yet. Degg
Network Administrator

 

[BuckWeet]

Degg, you can do the DHCP for all vlans anyways with the "ip helper-address" command..


I use the intel NIC in my home pc.. I have 1 interface made for my public IP to the cable modem, then the 2nd interface is for my internal wan.. it rocks. only need 1 network card in my box..


BuckWeet

 

[SoyGalesa]

Thanks for the info so far. Is it true to say then that you apply an IP address to every VLAN that the card can receive, based on the VLAN's you trunk to it from a switch.

 

[BuckWeet]

Correct

BuckWeet

 

[SoyGalesa]

Thanks Buckweet you have confirmed what I suspected. Now all I have to do is convince the server guys that their server is causing my RSM utilisation issues.

 

[pablow]

OK, I've now got a dot1q aware network card (Intel Pro/100 S) running under W2K and all is well. I have configured each VLAN that this card can see and all the IP addresses are OK.

Next question is, how do I set up the DNS (Netware DNS that is) to supply the correct address based on the VLAN of the clients???

All help gratefully received.

 

[Degg]

do you have a different dhcp pool for each vlan? I believe the packet coming in will have the ip address of the vlan it came from, so you just have to set up dns in each dhcp pool and the clients will get a dns address based on which pool it gets an ip from. Degg
Network Administrator

 

[sasj0e]

Hey I have really a big doubt about the working of vlan aware network cards.
If set a network card part of several vlans,then even after trunking the switch port,it could not communicate with the other vlan clients.I think this can not be done using a layer 2 switch like cisco 4006 with sup-II
Just a input....any body has suggestion on this?
sas

 

[BuckWeet]

Huh? Yes it does work..

Basically what happens if that you make virtual interfaces for each vlan that you want to work on. And then if it needs to talk to vlan 10, it tags the 802.1q frame with vlan 10. the switch recognizes it and switches the frame to whatever vlan 10 participant is needed.


I used this on my network at home. I have an internal LAN, and an external lan that is connected to the Cable modem (so i have can a public IP on that machine) It works great, plus alleviates the need for 2 network cards, and also the need for the 2nd IRQ (since i don't need 2 network cards)


BuckWeet

 

[sasj0e]

Buckweet,
Could you please let know,how do you achieve this?Is there anything to be set specifically in switch to get this done.
If I create 2 virtual interface with two different vlan ids,any thing else to be done in switch port so that, communication happens to other vlans(other than native vlan).
Please let me know,this would be a great help to me,
Thanks,
Sas

 

[BuckWeet]

Yea, you have to setup the port on the switch to be a 802.1q trunk port, or multi-vlan capable port..

for example:

PC with VLAN NIC
Interface Fast 0/1
switchport mode trunk
switchport encapsulation dot1q


Normal PC that is on vlan 10
Interface fast 0/10
switchport access vlan 10



BuckWeet

 

[sasj0e]

thanks Buckweet,
But still I find little difficutly with Cisco 4006 with Supervisor engine 2 and catos 7.3.
If you have some more patience pls let me know, how do I configure in Cisco 4006?
If I have server with NIC configured for 2 vlans, 2 and 3.
if I have a client machine on vlan 2.How do I configure on switch ports (both client and server)so that client machine on vlan 2 recieve/send packets from/to server.Native vlan being 1 (default and is same for sc0).
Thanks in advance,
sas

 

[BuckWeet]

well to do catos you need to do like "set trunk"
or "set vlan"..

But what it sounds like you want to do is make a system on vlan 2 talk to vlan 1. if you want to do that, then you need some kind of layer 3 device. whether it be via a router or a sup engine that supports L3 switching..


BuckWeet

 

[Lequang]

Hi, very interesting. Let say you have a distribution switch (DS)(or edge) and a core switch (CS) where you connect your server farm. The scope is to connect client wrkstn to DS and make them reach the server farm.
On DS you can create vlanA and B and assign ports to each vlan.
On CS you have to create Vlan A and B and C which is the vlan of the server farm.
ON DS you can have Uplink GBIC to CS.
In CS you route between Vlans (L3 switching).
You might have a DHCP server with scope for vlanA and Scope for vlanB. This concept works very well.