for the last few days I have been trying to setup traffic shaping and artificial latency in a local network. Currently I have an Ubuntu 20.04 PC with 2 NICs, where one is connected to the company network and the other shares the connection with an arbitrary number of clients(all with static IPs) through a switch. Currently I have gotten as far as successfully sharing the connection with the clients, introducing latency and shaping the download speeds using netem. Here comes the problem, I can't seem to shape the upload traffic the same way as download traffic. What I have tried so far:
sudo tc qdisc add dev enp4s0 root handle 1: priosudo tc filter add dev enp4s0 protocol ip parent 1: prio 1 u32 match ip dst {CLIENT IP} flowid 1:2(down)sudo tc filter add dev enp4s0 protocol ip parent 1: prio 1 u32 match ip src {CLIENT IP} flowid 1:2(up, doesn't seem to work)sudo tc qdisc add dev enp4s0 parent 1:2 handle 20: netem delay 50ms rate 100mbit
Furthermore, while I was looking for solutions I found here that the default number of bands is 3, so this means that by default I can have 3 netem qdiscs to shape traffic with. Apparently if I change the number of bands in the first line using the argument bands X I need to edit the priomap too, but after doing it, it seems that everything works just like before. I sadly can't seem to find an answer as to why this works like that.
Is my approach to the problem correct? Would this be scalable? I don't think I will ever need to account for more than 20 clients at once so I assume it can be automated pretty well with some scripts later on. On the other hand is there a better way to achieve what I need, that I'm not aware of. I am very new to this topic so any advice is appreciated, thank you in advance.
