a client of mine purchased a CCR1009-7G-1C-1S+ (Mikrotik Core router)
Now currently there is a fiber connection with the ISP router setup in bridge mode right in fornt of the client's Mikrotik router.
The ISP router connection is connected to the Lan port 1 of the unit and is operating as the wan port.
Everything appears to be working as intended. However only Facebook has an issue where it isn't loading images or videos.
I should mention everything was working correctly beforehand (on the previous ISP's connection), but the client switched from a PPPoE internet connection recently to the new fiber connection.
Once they switched to the new ISP, I disabled the PPPoE connection and directly placed static IP's provided by ISP into the mikrotik router for internet connection.
At first I thought maybe there is possibly some firewall rule causing havoc.
Saved the settings to a backup file, reset the entire router, insert static IP from ISP into the router to get the internet working.
Immediately with no firewall rules in place I am already receiving the same issue.
we have taken the ISP router out of bridge mode, bypassed the Mikrotik unit and plugged it directly into the client network, Facebook then works perfectly.
But we require the Mikrotik unit for a site-to-site vpn as well as mac users are using L2tp/ipsec VPN's to connect remotely for work.
I have tried replacing the default DNS addresses from the ISP with ones from google and openDNS.
I've read online that it could be the MTU's for the network ports. I've changed those and it made no difference.
I've also read on another forum topic post that too many device in a chain doing natting can cause this issue.
I'm basically stuck right now. I've spoken to people on the Discord Forum group MikrotikZA. They recommend I remove the ISP router completely and plug the fiber directly into the Mikrotik.
The mikrotik software package is on the latest stable version.
DHCP and DNS services were hosted by one of the clients servers. I disabled those services temporarily and enabled them on the mikrotik and it made no difference.
I am running quite a few clients using fiber via Mikrotik routers (Normally Hap lites or Hex S, including my own premises).
This is the first case where I run into this issue.
I'd just like to know if anyone has any other advice or tips on things I could check.