Combining two ISPs in one router (or two)?

Skip to first unread message

Robin Goodfellow

Sep 22, 2021, 8:46:42 PM9/22/21
I don't know anything about routers where we have two ISP's one of which
sucks most of the time but their power stays on strong when the PG&E power
goes off (which is a LOT in the Santa Cruz Mountains of California).

The other ISP is great most of the time, but he doesn't have battery backup
so when the power goes off, their relative strengths cross.

Meanwhile if I subscribe to both, I kind of want to have both when all is
well in PG&E land. There are others in the same boat, so that's why I ask.

My question is if I add the second ISP, folks tell me I should set up two
separate routers, or, get a dual-wan router.

How well does the dual wan router setup work?
Does it combine the bandwidth or just one at a time?

Which would you choose if you have the choice of two routers or a dual-wan
router (or does it not matter)?

Any experience you can share?

Char Jackson

Sep 22, 2021, 11:00:24 PM9/22/21
I know you don't read my posts, but I'll still put this out there.

There are commercial products that work, but I would recommend a homebrew
solution based on pfSense. You can set up dual WAN connections, each to its
own ISP, where both ISPs are used as long as both are available, but if
either ISP goes down pfSense will automatically use the one remaining ISP.
Each ISP is monitored, via ping to a WAN IP, so if ping is successful the
ISP is assumed to be available.

Note that, due to the nature of TCP connections, WAN failover won't always
be entirely seamless, so expect to reestablish a connection in some cases.

To get started, you need a PC with 3 NICs, two for WAN and one for LAN, and
the free pfSense software. One example of the dual-WAN configuration is

TIP: You can configure "dual-WAN + 1 LAN" with just two NICS or even with
just one NIC, but the config guide above is written with 3 NICs in mind.
Separate NICs for each of the 3 networks will be easier to set up.


Sep 23, 2021, 4:05:36 AM9/23/21
IMHO the simplest and most reliable way to do this is to just get an uninterruptible power supply (UPS) for your non-battery router.

I've been doing this for years and it's quite reliable.

A cheap 350VA is plenty good.

Andy Burns

Sep 23, 2021, 4:52:37 AM9/23/21
And if the ISP's kit in the street loses power, what does your router talk to?

Char Jackson

Sep 23, 2021, 10:18:09 PM9/23/21
Exactly. A UPS doesn't solve the problem.

In 2004-2006 I had 6 WAN connections, two each to three ISPs, but I didn't
have link monitoring or automatic failover configured at the time. I was
only doing it to get additional download bandwidth. For that, it worked
very well.

Robin Goodfellow

Sep 24, 2021, 12:56:17 AM9/24/21
Andy Burns <> asked
> And if the ISP's kit in the street loses power,
> what does your router talk to?

I asked some neighbors who sent me the following information.
What do you think of this added set of suggestions from two neighbors?

Neighbor 1:
I use the Peplink Balance Pro 30.

I did have two units fail and replaced under RMA. Not something I would
expect in this price/quality range. The third one is going on a year plus
and has not had an issues.

I currently have 3 WAN connections. It works as advertised.
The failover takes up to 10 seconds and is annoying, but does fail over.

Banding of the WAN connections is not available w/o a similar router at the
other end (useful for office to office comms, but not particularly for a

Neighbor 2:
Actually, i believe you can bond them via the SpeedFusion feature with the
Peplink Balance 30. It's an add'l license you have to purchase.

Also, in the Peplink Balance 30, you can adjust the failover time AND you
can also set up alerts so you get an email when one of the connections goes

Here is the link about SpeedFusion:
Reply all
Reply to author
0 new messages