Question No internet after connecting 3rd WAN to R470T+

Feb 23, 2020
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Hello Everyone
I have:
Model: TL-R470T+
Hardware Version: V6
Firmware Version: 6

I have a problem connection my 3rd WAN line to R470T+ and stay connected.

my configurations are as follow

1- ADSL Router - 192.168.2.1 >> WAN 1 Port

2- ADSL Router - 192.168.3.1 >> WAN 2 Port

3- 4G Router - 192.168.4.1 >> WAN 3 Port



Everything works fine until I connect the 3rd WAN to the load balance, it connects and get IP address but at this moment I lose my internet connection, the internet only comes back again when I disconnect the WAN 3 physically or from the WEB console from the R470T+
anyone have any tips about this issue?
Regards.
 
It likely a issue with how you are attempting to spread the traffic over the links. I would first suspect a DNS issues but it depends if you force the traffic by source address or destination.

The only way these units work well is as primary/back. Trying to run them as active/active is a massive undertaking. The main problem you have is that the wan ip addresses are different on the different connections.

The example that many people understand on this forum is a game server. Most you login to some authentication server. You then start your game on some form of world server. If the traffic going to these 2 servers use different connections they will appear to come from 2 different users (ip addresses) and the game company will drop it.

It tends to be very tricky to prevent this problem. The router can't know all the possible limitation between ip addresses. The other method assigns machines in your house to only 1 connection but that is little different than plugging it directly into their own internet router directly.
 
Feb 23, 2020
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@bill001g
Thanks for your reply, but the probelm happens even if there is no active internet connection on wan3, once I conncet a router to this port and I got no internet, I am not merging any WAN together on the configuration, I am just making a routing policy and a backup wan line in case on drops.
I don't know if there any other configurations I should pay attention to, I even tried to connect another normal router not 3G one to WAN 3 and this router has no internet connection and I am still get disconnected once this WAN3 kicks in.
 

SamirD

Honorable
Jan 16, 2014
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Are the first 2 connections from the same ISP and the 3rd a different one? Then it's probably a DNS issue and not actually an access issue.

I've used various multi-wan routers for decades and this is still a common problem because isps make their dns servers accessible only to their own customers in order to limit traffic to them. My solution that I've implemented on many setups is to simply hardcode 8.8.8.8 as the dns server in the router and have it hand that out to the clients versus what comes from the isps, which will vary depending on which isp is active on that particular connection.

A quick experiment to confirm all this would be to ping a known name/ip and record the ip address. Then plug in wan3 and try to ping the name again, and it should fail. Then ping the IP address and it should work.

Then on the computer, manually change the dns server to 8.8.8.8. Try the ping to the name again and it should work as well as full Internet access.
 
Feb 23, 2020
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First of all thanks all for your help .



It is working now, what happens is that I was connecting my router to WAN3 and this router doesn't have active intertnet, for some reason the R470T was favoring WAN3 port over the other two so I got no internet.

I fixed this issue by making a routing policy as the backup link didn't fix this either.

Now I have a group policy for all the computers to use WAN1,WAN2 and it is active.

thanks again for the help.
 
This is why real routers run routing protocols. The ethernet port likely will never go down so it is a bad indicator to use to switch connections. These type of devices sometimes can run ping to some internet ip to see if it can pass traffic but it will never compare to receiving routing updates that can show issue far into the path.
 
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