Network configuration - howto define interface connected with another LAN



I’m planning the following network architecture:
WAN <–> NethServer NIC red with static IPv4 <–> Nethserver NIC green
WAN <–> Router with Dynamic DNS <–> LAN

How must I configure another NethServer NIC to establish connection to LAN
Red, green, blue or orange?

For me green looks to be most adequate… can you confirm?


(Gabriel GHEORGHIU) #2

Hi @cmonty !

I understand that you have two WAN connections in the same location?
Why do you want to use two NS?
Can you be more specific?

Anyway, it depends by how do you want to use the NS on the second connection.

If you use your router as Firewall/UTM, you can choose GREEN.
If you use your router only for NAT (any to any) and you want to use NS as Firewall/UTM, you must choose RED and the others NICs that are on NS, GREEN (LAN), ORANGE (DMZ) or BLUE (WLAN Guest, generally).

Kind regards,


My ISP offers static IPv4 address.

I was thinking to assign NethServer red to this static IPv4 address bypassing the router.
This means the router offers function “bridge” and hereby acts as modem only.

In the end I will have direct internet access with NethServer over static IPv4 + internet access with router using dynamic public IP.

The network behind the router is a private LAN equal to the green network of NethServer.

How can I connect these two networks?

(Gabriel GHEORGHIU) #4

So, you want to connect with

Something like this?

(Gabriel GHEORGHIU) #5

I read your posts again and I’m a bit confused.

Do you have two ISPs? One (WAN 1) who gives you static public IP address and another (WAN 2) who gives you dynamic public IP address (PPPoE, DHCP)?


I’m sorry for causing confusion.

Technically there’s only 1 ISP, and the contract includes 1 static IPv4.
This static IPv4 is bound to a MAC, and I need to maintain this with the ISP directly.

In theory I can maintain the MAC of router or any other MAC.
I decided to maintain the red NIC of NethServer, connect this NIC with the router and bridge the relevant port internally in the router.
Hereby the router is bypassed by any traffic going through this port and only acts as a modem.

In this picture the host would be represented by NethServer.
And there’s another LAN provided by NethServer green NIC ->

If you think this makes sense, there’s another question.
NethServer is running on a VM (KVM) with 3 virtual NICs.
Should I maintain the MAC of virtual NIC (red) or the MAC of physical NIC bound to virtual NIC?


(Rob Bosch) #7

I don’t exactly understand your picture. Why do you create 2 devices where you have only 1 device? The Fritzbox is a modem/router, but when you (or your ISP) put it in bridge mode, the router function will be disabled and the IP address received from the modem will be passed on to the first device connected after the Fritzbox (= your NS)

(Gabriel GHEORGHIU) #8

Look at my picture from here:
(Sharing good Nethserver installation combinations SME with explainations)

It is what do you need.

As @robb said:

You will connect NS RED NIC to your modem (PPPoE in my picture).