Two WAN ports and load balancing

Hello all,

As some of you may know, Tp-Link Archer C7 v5 has only one "official" WAN port.

My motivation to flash OpenWrt is to reassign a gigabit LAN port to act as a second WAN port.
Then, somehow configure the device to do load balancing or, at least, perform an automatic switch of the internet provider (WAN1 or WAN2) if the active one goes down.

Is that even possible?

Thank you very much.

Yes this is straightforward. Under OpenWrt the Ethernet switch is fully configurable so that any of the 5 ports can be used for any network. Add an extra wan network then use the mwan3 package to load-balance them.

3 Likes

Ok, it does seem straightforward! I have already flashed OpenWrt and already loving it. Is there any guide or tutorial I may follow to enable the second WAN port and mwan3 usage? I'm a total newbie on OpenWrt.

Thank you!

I'm interested as well. Just got openwrt running on a ER-x. Quite a steep learning curve even for a technical person.
I've got two WANs- BT VDSL and Backup 4G (LTE). Just running on the BT VDSL at the moment, and trying to work out how Openwrt defines the gateway to use.

What I found so far:

mwan3 documentation
Notes on VLAN. Installing mwan3 involves reconfiguring the switch to add other WAN port(s) first

The second ISP is not installed yet here at my office, so for me, this is entirely theoretical. It still seems straightforward, but a steep learning curve indeed.

2 Likes

I will test later and let you know the outcome. I can't test during the day- my wife is sign language interpreter so the internet service is essential for her work. I was dicing with death restarting the IGMPPROXY while she was working yesterday.

Hi Roy,

I followed this video Mwan3 Failover .There are also comments below the video for other scripts if you need VPN resilience.
Looks good at the moment.
I need to test further tomorrow.

Regards Phil

Hi Phil, thanks for the follow-up. Reading the abovementioned resources, I've finally realized how to configure WAN interfaces and mwan3. I now have three WAN interfaces: two load-balanced cable connections from different providers ("wan" and "wanb") with 40/60% weight and a 4G failover as a backup if both fail ("wanc").

I'm still don't have the second cable ISP to do a full load balance testing and have problems with the failover. It seems "wanc" stops working as a gateway every time I disconnect "wan", preventing any traffic through "wanc", this, in turn, causes "wanc" to fail the online testing (ping to the internet). I'm attaching my current configuration; perhaps I'll help in a further discussion.

I'll get back when these problems got sorted out.




2 Likes

Thanks Roy,
Funny last night I was streaming a sport channel to my laptop and I did a DSL modem reset to clear an error. I was expecting the stream to stop, and it continued. Then I remembered I'd setup the auto failover :slight_smile:

I was having some weird issues with intermittently not being able to join Zoom and Whatsapp media not downloading. Anyway removed SQM and any IPv6 stuff- all seems ok now.

I also noticed in LUCI that I can't change the tracking method from ping. There seems to be other options via CLI but they're not available in LUCI. Ideally i want to track PPPoE status.

I'd also like to test if a Zoom video call stays up if my primary ISP fails. Something for next week.

Hi Roy,

Tested again this evening and it works like a dream. I started a Zoom meeting, and shared a video. I also had a constant ping running in a command window. I stopped my primary ISP interface, the Zoom session stayed up and continued playing over my backup 4G LTE.
The ping lost one packet and the reply time adjusted to the LTE backup- from 8ms to 20ms.
Restarted the primary ISP interface, everything recovered correctly.
Just need to work out how to send an email notification if the primary fails, otherwise I wouldn't know its down! :slight_smile:

1 Like