What is the correct way to start a container with a given command?

Question

I want to create a set of containers for simulating network traffic. Inside each of the containers, I would like to set a different network delay. Right now I am doing it manually using this command, after logging into the container:

 sudo tc qdisc add dev eth0 root netem delay 128ms

I want it to be done automatically. Right now I am thinking about doing it like:

ssh root@container "my_commands"

but I am thinking about creating an instance of the container automatically (not that I am going to create many containers, each having different delay), so that later I would only have to start it.

What would be the correct way to configure it?

Answer 1

lxc-attach allows you to run a command in a container without logging in.

lxc-attach -n container-name -- <command>

So I guess you need to run:

lxc-attach -n container-name -- sudo tc qdisc add dev eth0 root netem delay 128ms

the output of the command, if any, is redirected to your standard outputs.