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to connect 2 routers with completely different IPs' to one modem

Discussion in 'Other LAN and WAN' started by TonyMY, Sep 19, 2018.

  1. TonyMY

    TonyMY New Around Here

    Joined:
    Sep 19, 2018
    Messages:
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    Is it possible to set up a network that will allow me to have two completely different connections out of 1 modem?

    1st connection will be used without any special settings (modem -> router#1 -> pc/tablets/smartphone/tv)

    2nd connection should have permanent VPN enabled within router (modem -> router#2 (IP assigned by VPN) -> tablets/smartphone/tv)

    The idea is that I could switch my devices between these two routers in case I want to use VPN or not.

    Here is why: I want to use some apps on TV that are available only in certain regions of the world and are not available in my region.

    I could have just one modem and router with preset VPN IP that allows me to choose IP/Region I need. As the result TV will show apps I need. However in order to get back to my own region or to other, I would have to reprogram modem and kill/turn on VPN tunnel (through logging into router from my PC) which is very inconvenient. Instead I prefer just go into internet settings on TV and choose which internet/router I would like to connect to.

    If I buy second modem will I be able to create network with settings described above?
     
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  3. ColinTaylor

    ColinTaylor Part of the Furniture

    Joined:
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    Location:
    UK
    It would depend on your ISP and the modem. Talk to your ISP.

    In my own experience the cable modem supplied (and its associated account) are configured to provide a single WAN IP address to the premises. If I wanted to have a second WAN IP address my ISP would install a second modem and charge me an additional fee. From what I've read on these forums there a some ISP's in the US that provide multiple IP addresses through a single cable modem.
     
  4. CaptainSTX

    CaptainSTX Very Senior Member

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    If you want to run to seperate networks and can get by with only having a single public IP then double NATing could work. The second network's WAN IP would be an IP from the first router's LAN DHCP range. The downside is that devices on the second router would be able to see devices on the first router's LAN unless you are able to set up VLANs on the first router and assign the second router to a VLAN without access to the first router's other VLANs. But if you can setup your VLANs correctly it might not be necessary to do anything else.

    If you want to run a WEB server on the second router's subnet or access other ports it will be difficult if not impossible and still isolate the two networks from each other.

    However, double NATing will not increase the latency of devices connected to the second network.

    It just depends on what you want to accomplish with your two networks if double NATing will work for you or perhaps just VLANs.
     
  5. TonyMY

    TonyMY New Around Here

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    Sep 19, 2018
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    thank you for your comments!

    My goal is to have 2 routers running in parallel. So I can connect to one or another any time I want (each router will have its own password and IP)
     
  6. CaptainSTX

    CaptainSTX Very Senior Member

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    A double NAT setup can handle that. My suggestion is just put your least secure devices, IoT devices and guest networks on the first router and your more secure devices on the second double NATed router and disable the setting allowing admin access from the WAN and you will be good to go.
     
  7. TonyMY

    TonyMY New Around Here

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    Sep 19, 2018
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    thank you! any chance you would be able to send some instructions (may be links) on HOW set up double NAT? I tried to google it and everything I can see is about how to fix double NAT, not how to set it up..
     
  8. degrub

    degrub Very Senior Member

    Joined:
    Dec 21, 2015
    Messages:
    633
    connect the WAN port of the first router to your ISP modem LAN port. Connect the WAN port of the second router to a LAN port on the first router. Disable "remote connection" on the second router. Done.
     
  9. HeMaN

    HeMaN Regular Contributor

    Joined:
    Jun 30, 2016
    Messages:
    56
    i have a something similar setup with the use of one modem, a small router/pc with pfsense, ubiquity ap's with multiple ssid's.

    I created multiple vlans each connected to a different ssid. on the wan side of pfsense I created an interface connected to the vpn provider.
    routing one vlan to the vpn, other vlans to the unencrypted line.

    for this setup there is a how-to available that is not very difficult to follow. If interested I can add that later to this post when I have access to my pc at home

    Verstuurd vanaf mijn SM-G955F met Tapatalk
     
  10. CaptainSTX

    CaptainSTX Very Senior Member

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    Here is my write up on why and how to double NAT
     

    Attached Files:

  11. TonyMY

    TonyMY New Around Here

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    Sep 19, 2018
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    thank you everyone! It works via double NAT.
     
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