This question is not similar to my earlier post. This is pretty simple I think, I just don't know enough about networking and the ubuntu firewall.
I followed this article and setup a linux container inside my ubuntu server on ec2. I can access the internet from my container.
| ----Ubuntu Server on EC2 -----
==== INTERNET <==== > | some magic routes traffic <=== lxc container
| [192.168.3.1]
|------------------------------
I needed the internet inside the container only to install dependencies for my app. Now I need to shut off internet access. I wouldn't mind any other approach like prevent a certain user account from the internet.
This is how the network config goes, Any ideas, clues or suggestions on what I should read will be appreciated :
There is a network bridge :
brctl addbr br0
brctl setfd br0 0
ifconfig br0 192.168.3.1 up
Then I did this:
iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE
sysctl -w net.ipv4.ip_forward=1
Then this : cat /etc/dnsmasq.conf
domain-needed
bogus-priv
interface = br0
listen-address = 127.0.0.1
listen-address = 192.168.3.1
expand-hosts
domain = containers
dhcp-range = 192.168.3.50,192.168.3.200,1h
Then : cat etc/dhcp3/dhclient.conf
prepend domain-name-servers 127.0.0.1;
prepend domain-search "containers.";
Then I ran :
dhclient -e IF_METRIC=100 -pf /var/run/dhclient.eth0.pid -lf /var/lib/dhcp/dhclient.eth0.leases eth0