I have the same problem with VirtualBox Linux VM, was wondering what is going on, and this post comes up. I am not sure if it is the same reason. I tried: tc q

I have the same problem with VirtualBox Linux VM, was wondering what is going on, and this post comes up. I am not sure if it is the same reason. I tried: tc qdisc add dev eth0 root netem delay 100ms and: printf 'HEAD / HTTP/1.0\r\n\r\n' | nc -6 rachelbythebay.com 80 returns nothing whereas printf 'HEAD / HTTP/1.0\r\n\r\n' | nc -4 rachelbythebay.com 80 returns as expected. In my case, firefox has no problem if invoked from command line, but "sometimes" it just hang up when invoked from script.