Rb5009 and gpon sfp = no internet only one device

[kenjessa]

I have a MikroTik RB5009 router, and I’m using a GPON SFP module for my ISP connection. When I connect the SFP directly to the RB5009:

Most devices on my LAN can access the internet without any problem.

However, a single specific device cannot access the internet, even though it gets a valid IP address, gateway, and DNS from the RB5009 DHCP server.

This device can still reach the RB5009 LAN interface, so local connectivity works fine.

When I use the ISP-provided GPON ONT and connect it via Ethernet to the RB5009, all devices, including the previously failing one, can access the internet normally.

I have tried everything that could possibly be tried.

[sppmasterspp]

What is your ISP ONT device, what is the device that cannot access the internet and how do you test - ping, traceroute?

[kenjessa]

What is your ISP ONT device, what is the device that cannot access the internet and how do you test - ping, traceroute?

My isp ont is nokia g-010g-r, only one device cant acces is realme c25s, i using alcatel g-010s-p with fs.mod v5, mobile can ping rb5009 and rb5009 can ping mobile but cant internet.

I watched the sfp with torch and rb5009 is actually outputting but not getting a response back. I think the sfp has a software or chip bug and is not passing a certain device.

[sppmasterspp]

Probably it could be better to ask on Mikrotik forums too. I have RB5009 running OpenWrt which I consider is superior to RouterOS.