@Carlootje 

 

You are problably behind a cgnat. very common on 4g. you have to speak with your 4g provider and ask for apn with public ip

 

  @MR.S 

 

dear sir,

when I connect also my laptop on the LAN I can make the same L2TP connection without a problem. So then the proble, I think isn't at the provider is it?

 

when setting up the L2Tp connection you cannot choose USB but only WAN. When the USB modem is connected and I check the status it's getting an IP etc. But the WAN CONNECTION stays down. Logical of course but is the L2TP also trying to go out through the interface USB?

  @Carlootje 

Carlootje wrote

  @MR.S 

 

dear sir,

when I connect also my laptop on the LAN I can make the same L2TP connection without a problem. So then the proble, I think isn't at the provider is it?

 

when setting up the L2Tp connection you cannot choose USB but only WAN. When the USB modem is connected and I check the status it's getting an IP etc. But the WAN CONNECTION stays down. Logical of course but is the L2TP also trying to go out through the interface USB?

OK, you have problably multiple problems, I guess you not have a public ip on 4g, but if you can not choose USB as WAN on L2TP server there is no need for public ip. 

Mybee a bug i dont know. 

 

You have a very old firmware, never updated so a new firmware is recomanded.. mybee ther is a fix on your problem.

 

 

 

  @Carlootje 

 

I try enable USB on a site, but there is no option to use this as wan in any vpn configuguration,, so it look like that usb is primary for failover to give internet when main line is down.

I have not tested USB myself so I have not mutch experiens with this.

 

  @MR.S 

 

I update the firmware but still same problem. Underneath screenshot of the Actual status with USB connected and working (Unless VPN outbound). Is there a way to confirm that this is not possible or a bug. In my opinion this should work because therefor I plug in an USB for failover.

 

Forgot, so when USB is connected and my laptop is on a LAN of the router and VPN outbound connection can be setup without a problem. Only thing that is not working is that the router should do this itself. Setup is a VPN client L2TP

Forgot, so when USB is connected and my laptop is on a LAN of the router and VPN outbound connection can be setup without a problem. Only thing that is not working is that the router should do this itself. Setup is a VPN client L2TP

  @Carlootje 

 

Underneath the setup which is working when WAN is connected, my assumption was that USB would take over at faillure....

 

  @Carlootje 

 

OK, I misunderstood you a bit, you are going to use the router as an L2TP Client, then there is no need for a public wan ip.
the fact that you cannot set up usb as wan in vpn is probably a bug. I have tested a bit on the routers I have available ER8411 and ER707-M2 it is the same, I use a controller.

it is probably something you should ask TP-Link support about. I also see that there are more people with the same problem as you.

 

 

https://community.tp-link.com/en/business/forum/topic/612952

 

If it urgen for you, use a 4g router and connect this to wan interface then vpn should work as a workaround.

 

 

  @MR.S 

 

Yes that is what I am doing now so I have a work around. But since two years we have suddenly an USB with 4G wich is good but in this way not working.