Using a powerline adapter and wireless bridge together as failover or loadbalancing

Question

I have two routes via ethernet. One is more stable but slow, the other is fast but might disconnect. What solutions are available to have a load balancer or fail over? The routes are both from a single router.

My current setup is: pfSense -> Wireless AP -> SwitchA -> powerline A powerline B -> SwitchB -> PCs in room

Powerline A-B gets 20mbit Basically I want to add a wireless bridge that also connects to switch B. powerline B -> SwitchB -> PCs in room Wireless Bridge -> SwitchB -> PCs in room

The switch by itself doesn't know which route to use (I assume), would a dual wan router with disabled DHCP work in this case or there a better solution?

Answer 1

You have not provided nearly enough information to go on - particularly how the "disconnect" works. Making huge assumptions there are a few ways to deal with this -

1. Ensure the more reliable route is less preferred and set the faster but less reliable connection up in such a way that the interface (or at least its route) disappears when its not available - this will provide automatic failover and give you largely the best of both worlds - but it assumes you can make the route disappear (which is not hard if you are using PPP. (Note that ethernet does not preclude the use of PPP, PPPoE is very common)

2. Use dynamic routing like BGP (or OSPF or RIP, but in reality it will be BGP on the assumption your routes go to different providers). This of-course assumes your router is BGP capable, you own rights to IP space and both providers will play together.

3. Set up source routing so packets can go through either connection depending on the source IP (or mark) assigned to them. Then balance this connection. Again, there are multiple ways to do this depending on what you are trying to do and your hardware ability, but include:

   1. Routes which require low bandwidth or high reliability go through the slow connection. "Nice to haves" go through the fast connection.

   2. Get an reliable offsite connection (virtual server), set up 2 VPN's to the server - one through each link, aggregate the links as and available and route everything across them. This probably offers the best of both worlds but requires quite a bit of skill and, of-course, a fast connection on the other side. [ And yes, I know someone doing just this, so its quite practical with the knowledge ]

In order to do any of this stuff you need a decent router - but decent could be a Linux based embedded system (I've done all of these things at one time or another using Linux). The exact howtos are not really amenable to a Superuser question as they require an in-depth understanding of networking.

Answer 2

I don't quite follow your diagram, but assuming you're talking about local networking, and not two seperate WAN uplinks, I suggest get decent switches that support OSPF, and let them do the hard work.

OSPF correctly configured will also occasionally exceed the bandwidth of a single link depending on your network topology (consider 4 nodes as 2 pairs, each node wired to a switch, and each pair also cross-connected), while other setups won't.