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How can I (if it is possible) to set up the network gateway if I have 2 internet lines from 2 different ISPs? Furthermore, one of them is forwarding /28 static ip for (into) our network. Is there a schematic diagram to refer to?


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up vote 5 down vote accepted

Using two or more ISPs is totally feasible, normal and even encouraged. You can:

  1. Use one ISP as primary route and have the second take over if the first fail.
  2. Use two or more ISPs to direct specific traffic (like, all youtube traffic goes to ISP 1, the rest to ISP 2 and so on)
  3. Use two or more ISPs at the same time with load balacing and failover (but that may require use of advanced routing protocols like BGP)

How to set it up will depend on what you are using to route the traffic. If it is a linux box you can refer to the Linux Advanced Routing & Traffic Control guide (section 4.2). For other systems you will have to look for some documentation.

I didn't get what you said by schematics, /28 means 16-2 valid ip addresses, but theoretically each ISP must give you at least one valid IP to work with.

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You can use two lines, in fact we have two lines here, to two different ISPs over different media.

However, you can NOT bond these disparit networks together (to combine two 10Mb links into a 20Mb link). At our router, we split traffic based on either destination, or if no specific destination, then round robin.

Regarding the /28 - this is no problem because as I mentioned the two links have to stay seperate.

All you'll need is a multi-WAN aware router, such as PFSense or a Netgear FVS336G

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