I’ve been looking through the docs but can’t find information on how we can set a MTU value. Does Mediasoup support this as a config option?
No. There is a const MTU_SIZE=1200 AFAIR which is static and the same value that libwebrtc uses.
ok, do you have any advice on forcing the MTU? I have packets being sent close to 1500 which is past the limit for a number of clients.
mediasoup never sends a packet bigger than 1200 bytes and there is something called IP fragmentation that works transparently at IP level for decades (unless clients or service providers block ICMP “for WRONG security reasons” so they kill the MTU discovery mechanism which is based on ICMP.
Yes, I’m pretty sure this is what’s occurring in my situation. I’m just having trouble finding a work-around.
Try sending pings (which is ICMP as well) to client’s public IP from your backend to see if it’s blocked.
BTW there is nothing else mediasoup can do here. Clients send packets of up to 1200bytes and mediasoup cannot make them smaller before relaying them to those other problematic clients