2nd WAN detected as DOWN on 1st WAN failover


Running on my Balance One I have two WAN connections (1st is an aerial antenna and 2nd is a 3G/4G connection through a Vodafone router.

From time to time the 1st WAN is detected as DOWN (even when the ISP says it was not and their logs show they are right, but this is another question). Then, the 3G connection starts to work but almost inmediately is also reported as DOWN while it is not.

Here you are attacched my LOG, and the outbound configuration (first rule is to enforce traffic to the 3G route, as it was not reachable if I just designated 3G as a backup line).




Can somebody help me with this?.

Thanks in advance,


Hi there. First, I don’t think you have you vodaphone router as a backup. It was connected prior to failing the WAN test. You can actually make it a true backup - it won’t initiate the connection unless WAN1 is down.

Your priority rule will work like you want since you only want traffic to go to the vodaphone if the first WAN is down. It most likely would have worked, except your WAN2 also failed the DNS health check. I imagine you are using the google public DNS services on both WAN health checks?

Personally, I use a different health check approach. Since I am really wanting to know if my link is connected (both links go to the same ISP), I ping the default gateway of the modem. So, my router is, the ISP modem is, and the remote gateway for the modem is I set up a health check for PING to As long as my end of the connection is up, I consider that a valid link. There are too many variables involved with DNS. Some DNS servers will label you a nuisance if you exceed a certain number of queries per day (especially using the same request repeatedly). Basically, DNS has to make it to layer7 and then back down. PING stays in the first 3 layers - far less false negatives.

My advice would be to ping the google DNS and possibly OpenDNS on each WAN. OR, you can move towards a PING strategy. Chances are that both DNS services won’t fail at the same time. I am pretty sure google had an outage this week. YouTube had some issues with iOS apps.

Hope this helps.

Thanks for your response, @jmjones.

Just to clarify, the 3G connection is not working as a “pure” (in terms of peplink) backup because the 3G router did not allow to do it. It is a non-enterprise level router with a 3G USB stick attached and it drops connection when there is no traffic. Thus, I had to maintain it up to keep connection alive and make use of output rules. A workaround to start working. So no, it is not a pure backup but working as such.

Yes, I am using the Google ping on both links which now that you point it out, I am realizing is a nonsense in case they are not reacheable. So I have just changed to a mixed configuration with first url being one of my company (an external one on an independent hosting service) and the second url, that from google (

It seems reasonable you are right and Google (or an intermidiate service) is blocking us as link down always happen together on both links and almost at the same time everyday…

I will let you know how it goes tomorrow after I have changed it today.

Thanks a lot!

Still having problems :-(, both links are detected as down at the same time. The ISP says they have no mention to issues on the log… so it seems to be a problem with the aggregator.

I changed my configuration to do ping to my own server (outside the company network) and one from google. This is (again the log from the One):