Restrict Internet Access - Docker Container
As found here, I got this to work with docker-compose. Save as docker-compose.yml:
version: '3'
services:
outgoing-wont-work:
image: alpine
networks:
- no-internet
command: ping -c 3 google.com # will crash
internal-will-work:
image: alpine
networks:
- no-internet
command: ping -c 3 internal-and-external
internal-and-external:
image: alpine
networks:
- no-internet
- internet
command: ping -c 3 google.com
networks:
no-internet:
driver: bridge
internal: true
internet:
driver: bridge
Then run docker-compose up -d, docker-compose ps will show something like this after a few seconds:
Name Command State Ports
----------------------------------------------------------------------------------
dco_inet_internal-and-external_1 ping -c 3 google.com Exit 0
dco_inet_internal-will-work_1 ping -c 3 internal-and-ext ... Exit 0
dco_inet_outgoing-wont-work_1 ping -c 3 google.com Exit 1
Network creation for access internet
docker network create --subnet=172.19.0.0/16 internet
Network creation for block internet access
docker network create --internal --subnet 10.1.1.0/24 no-internet
If you want to connect docker container into internet
docker network connect internet container-name
If you want to block internet access
docker network connect no-internet container-name
Note
in internal network we can't expose ports to connect outside world, please refer this question for more details
Another option, if you need to expose ports on a container without internet access, but want to let it talk to other containers would be to provide a bogus DNS configuration. This isn't a perfect solution though, since it doesn't prevent direct IP access to the outside world.
docker-compose.yaml
version: '3'
services:
service1:
image: alpine
command: sh -c 'ping service2 -c 1; ping google.com -c 1'
dns: 0.0.0.0
service2:
image: alpine
command: sh -c 'ping service1 -c 1; ping google.com -c 1'
dns: 0.0.0.0
isolated> docker-compose up
Recreating isolated_service1_1 ... done Recreating isolated_service2_1 ... done Attaching to isolated_service2_1, isolated_service1_1
service1_1 | PING service2 (172.18.0.2) 56(84) bytes of data.
service1_1 | 64 bytes from isolated_service2_1.isolated_default (172.18.0.2): icmp_seq=1 ttl=64 time=0.038 ms
service1_1 |
service1_1 | --- service2 ping statistics ---
service1_1 | 1 packets transmitted, 1 received, 0% packet loss, time 0ms
service1_1 | rtt min/avg/max/mdev = 0.038/0.038/0.038/0.000 ms
service2_1 | PING service1 (172.18.0.3) 56(84) bytes of data.
service2_1 | 64 bytes from isolated_service1_1.isolated_default (172.18.0.3): icmp_seq=1 ttl=64 time=0.093 ms
service2_1 |
service2_1 | --- service1 ping statistics ---
service2_1 | 1 packets transmitted, 1 received, 0% packet loss, time 0ms
service2_1 | rtt min/avg/max/mdev = 0.093/0.093/0.093/0.000 ms
service1_1 | ping: google.com: Temporary failure in name resolution
service2_1 | ping: google.com: Temporary failure in name resolution
isolated_service1_1 exited with code 2
isolated_service2_1 exited with code 2
As stated in Bilal's answer, the internal network is a good solution if you do not need to expose the ports.
If you do need to expose the ports, the below solution using iptables does the job for my requirements:
docker network create --subnet 172.19.0.0/16 no-internet
sudo iptables --insert DOCKER-USER -s 172.19.0.0/16 -j REJECT --reject-with icmp-port-unreachable
sudo iptables --insert DOCKER-USER -s 172.19.0.0/16 -m state --state RELATED,ESTABLISHED -j RETURN
Then add
--network no-internet
when you run your docker container. For instance:
$ docker run -it --network no-internet ubuntu:focal /bin/bash
root@9f2181f79985:/# apt update
Err:1 http://archive.ubuntu.com/ubuntu focal InRelease
Temporary failure resolving 'archive.ubuntu.com'