Experimenting with network topology and throughput.

[agent_kith]

Here's a second experiment. What happens if I want to send something with a payload that's greater than 9000 bytes, but the receiving party cannot accept this number? For example with Raspberry Pis, the maximum allowable MTU is 1500.

Now the router will be smart enough to break it up into smaller packets and send it to the receiving party. The split up packets will be marked so that it can be re-assembled into it's original packets.

Like so, I am trying to send a payload of 9001 bytes to a machine with a MTU of 9000. If I have the "do not fragment" bit set, this original 9001 bytes cannot be split up and must be sent as is, or be rejected. But if I don't have this bit set, the payload can be split into 2. In Microsoft Windows, the "do not fragment" flag is -f. So with this on, trying to send 9001 bytes will fail, and succeed if off. Exactly as designed when I'm using Untangle as the router:
 

Frustratingly, I ran the same experiments before in pfSense, and it worked! Now this behaviour is intermittent and I have ny idea why. One thing that bugs me most is the use of "double negatives" in pfSense configuration. Turning something on (tick in a checkbox) means I'm actually turning something off!

There are features in pfSense that I will miss (HAProxy and ACME). But thanks to the generous support by you guys, I now have a Ryzen server with more grunt and RAM. I can now now create a new virtual machine to run HAProxy and ACME. In fact, I can even run the Untangle firewall as a virtual machine, keeping things even simpler!

I don't expect a lot of people to push their music setup to this extent. But if you are interested, remember to stay tune to the blogs to find out how I do it.. It'll also serve as a written record for me to refer back when things are broken again.