Hi Everyone,

I'm having a strange issue with the ER5120 model. The incident is repeatable 100%.

I have two different physical sites, each with similar topology. The ER5120 is supposed to connect to 2 WANs for Load Balancing purposes, and then provide its own LAN services (DHCP, BW control, NATs, etc.). I'm familiar with TP-Link technology and GUI, as I also have R480T+ and R470T+ in smaller sites. I just moved to the ER5120 because of the seemingly superior technical specs.

The thing here is that those routers eventually hang my ISP modems. They put them to a halt. I confirmed that because I disconnect the UTP cable from the router and try to get an IP directly with my laptop, but there's no response. When I call my ISP to ask about it, Support tells me that they lost connection to the device, with no other information available. I solve the issue temporarily by rebooting the modem, but after an hour or two the same thing happens.

What bugs me is that I don't have that issue with my smaller routers. The R480T+ handles just fine. If I just replace one model for the other in the rack, all problems disappear.

This particular issue is more frequent whenever the modem is in bridge mode. If it is in router mode (so it acts as a dhcp server itself), it lasts an entire day before having to be rebooted.

I have this particular issue with the same ISP and the same modem brand: Sagemcom. I feel the need to stress this out: the same issue occurs in two different, brand new routers, in different buildings.

Do any of you have a clue of where to start?

Thanks,

Hernan