Make docker use IPv4 for port binding

force docker to use ipv4
docker --ipv6=false
docker-compose bind ipv4
docker outbound ports
docker port mapping
docker run
docker ipv6
docker port mapping not working

I have docker host and inside I have one container.

The docker host is binding the port on IPv6 interface only, not on IPv4.

This is the output

tcp        0      0 0.0.0.0:22              0.0.0.0:*               LISTEN      -
tcp        0      0 0.0.0.0:55082           0.0.0.0:*               LISTEN      -
tcp        0      0 0.0.0.0:111             0.0.0.0:*               LISTEN      -
tcp6       0      0 :::80                   :::*                    LISTEN      -
tcp6       0      0 :::22                   :::*                    LISTEN      -
tcp6       0      0 :::40280                :::*                    LISTEN      -
tcp6       0      0 :::5432                 :::*                    LISTEN      -
tcp6       0      0 :::40122                :::*                    LISTEN      -
tcp6       0      0 :::36378                :::*                    LISTEN      -
tcp6       0      0 :::40543                :::*                    LISTEN      -
tcp6       0      0 :::111                  :::*                    LISTEN      -

Now I have 40122 port on host to link with port 22 on container.

I want to SSH into that container but I am not able to as its only bound to IPv6

This is my docker version Docker version 1.5.0, build a8a31ef

docker ps

201bde6c839a        myapp:latest   "supervisord -n"    3 weeks ago         Up 2 hours          0.0.0.0:40122->22/tcp, 0.0.0.0:40280->80/tcp, 0.0.0.0:40543->443/tcp   myapp

I ran using docker run -d -P -p 40122:22

netstat -tlna

tcp        0      0 0.0.0.0:80              0.0.0.0:*               LISTEN
tcp        0      0 0.0.0.0:22              0.0.0.0:*               LISTEN
tcp        0      0 127.0.0.1:3031          0.0.0.0:*               LISTEN
tcp        0      0 0.0.0.0:6379            0.0.0.0:*               LISTEN
tcp6       0      0 :::22                   :::*                    LISTEN
tcp6       0      0 :::6379                 :::*                    LISTEN

ps aux

root         1  0.0  0.8  52440 16668 ?        Ss   00:53   0:03 /usr/bin/python /usr/bin/supervisord -n
root        49  0.0  0.1  17980  3048 ?        S    01:32   0:00 bash
root        64  0.0  0.1  46632  2712 ?        S    01:32   0:00 su -l vagrant
vagrant     65  0.0  0.1  21308  3760 ?        S    01:32   0:00 -su
root       288  0.0  0.1  17980  3088 ?        S    02:01   0:00 bash
root       304  0.0  0.1  46632  2720 ?        S    02:01   0:00 su -l vagrant
vagrant    305  0.0  0.1  21304  3804 ?        S    02:01   0:00 -su
vagrant    308  0.0  3.7 429616 75840 ?        Sl+  02:01   0:05 python ./manage.py shell_plus
root       654  0.0  0.4  47596  9848 ?        S    03:12   0:01 /usr/local/bin/uwsgi --die-on-term --ini /var/www/conf/uwsgi.ini
root       655  0.0  0.3  90280  7732 ?        S    03:12   0:00 nginx: master process /usr/sbin/nginx
www-data   656  0.0  0.1  90600  3624 ?        S    03:12   0:00 nginx: worker process
www-data   657  0.0  0.1  90600  3624 ?        S    03:12   0:00 nginx: worker process
www-data   658  0.0  0.1  90600  3624 ?        S    03:12   0:00 nginx: worker process
www-data   659  0.0  0.2  90940  4500 ?        S    03:12   0:00 nginx: worker process
root       660  0.0  0.2  61372  5332 ?        S    03:12   0:00 /usr/sbin/sshd -D
root       669  0.0  0.4  37004  8892 ?        Sl   03:12   0:01 redis-server *:6379
root       856  8.0  2.8 388720 57792 ?        Sl   04:07   0:18 /usr/local/bin/uwsgi --die-on-term --ini /var/www/conf/uwsgi.ini
root       857  8.0  2.8 388720 57792 ?        Sl   04:07   0:18 /usr/local/bin/uwsgi --die-on-term --ini /var/www/conf/uwsgi.ini
root       858  8.0  2.8 388720 57792 ?        Sl   04:07   0:18 /usr/local/bin/uwsgi --die-on-term --ini /var/www/conf/uwsgi.ini
root       859  8.0  2.8 388720 57792 ?        Sl   04:07   0:18 /usr/local/bin/uwsgi --die-on-term --ini /var/www/conf/uwsgi.ini
vagrant    889  0.0  0.1  18692  2508 ?        R+   04:11   0:00 ps aux

As @daniel-t points out in the comment: github.com/docker/docker/issues/2174 is about showing binding only to IPv6 in netstat, but that is not an issue. As that github issues states:

When setting up the proxy, Docker requests the loopback address '127.0.0.1', Linux realises this is an address that exists in IPv6 (as ::0) and opens on both (but it is formally an IPv6 socket). When you run netstat it sees this and tells you it is an IPv6 - but it is still listening on IPv4. If you have played with your settings a little, you may have disabled this trick Linux does - by setting net.ipv6.bindv6only = 1.

In other words, just because you see it as IPv6 only, it is still able to communicate on IPv4 unless you have IPv6 set to only bind on IPv6 with the net.ipv6.bindv6only setting. To be clear, net.ipv6.bindv6only should be 0 - you can run sysctl net.ipv6.bindv6only to verify.

Port redirecting binding to IPv6 but not IPv4 interfaces. � Issue #2174 , That is, docker run is equivalent to the API /containers/create then /containers/(id )/start . --link-local-ip, Container IPv4/IPv6 link-local addresses. --log- This binds port 8080 of the container to TCP port 80 on 127.0.0.1 of the host machine. Use the docker port command to inspect the mapping Docker creates. Forward selectively. You can also specify ports. When doing so, you don’t need to use ports from the ephemeral port range. Suppose you want to expose the container’s port 8080 (standard http port) on the host’s port 80 (assuming that port is not in use). Append -p 80:8080

Setting net.ipv6.conf.all.forwarding=1 will fix the issue.

This can be done on a live system using sudo sysctl -w net.ipv6.conf.all.forwarding=1

Bind container ports to the host, By default, when you create a container, it does not publish any of its ports to a container using the --network flag, you can specify the IP address assigned to� Recommend:ubuntu - Server setup: Subdomain or different port for API and single or multiple ssl certificates for a docker, nginx, web and api setup is do I need one ssl certificate for the outside world connecting with the nginx layer or do I need one ssl certificate for the web application and one ssl certificate for the rails api answer 1 You can use the nginx as a load balancer fo

By default, docker uses AF_INET6 sockets which can be used for both IPv4 and IPv6 connections. This causes netstat to report an IPv6 address for the listening address.

From RedHat https://access.redhat.com/solutions/3114021

docker run, I have a simple Apache container that exposes port 80 running on … When I run the container, it only binds to the ipv6 address >:( I have firewalld If this works, you can make it permanent by adding net.ipv4.ip_forward = 1 to /etc/sysctl. conf. Make docker use IPv4 for port binding. Tag: ubuntu,docker,port,ipv6. I have docker host and inside I have one container. The docker host is binding the port on IPv6

Container networking, Is there a way to make it only bind to IPv4 interfaces? # docker run -p 8000:8000 - i -t colinsurprenant/ubuntu-raring-amd64 /bin/bash # lsof -OnP |� To bind the Docker container port 80 to the host system port 8000 and IP address 127.0.0.1 (a.k.a. localhost), just run the following command: docker run -d -p 127.0.0.1 :8000:80 nginx Conclusion

Need help! Docker only binds to ipv6 : docker, When port-binding with containers, docker seems to bind containers to IPv6 ports instead of IPv4 ports. I have disabled IPv6 via sysctls, but� The docker-proxy is the user space port forwarding process used by docker when you publish a container's port. Run a docker container ls to show all running containers, along with the ports each may be publishing, and stop the container listening on the ports you want to use.

Docker will only bind forwarded ports to IPv6 interfaces, In this blogpost I explain the concept of Docker Port Binding. I'll make sure I pour everything you need to know about this topic in your head. the host system port 8000 and IP address 127.0.0.1 (a.k.a. localhost), just run the� Be able to specify which ports docker/hyperv exclude or use, and/or I expect that docker/hyper-v actually use the ports that it is excluding and that they show up in netstat -ano as being used or listened on. Actual behavior. If I start a service that binds on port 50051 (it is a grpc service, and that is the traditional port used by grpc), it

Docker appears to bind containers to IPv6 ports instead of IPv4 ports , On linux, modern versions of docker support using iptables instead of a proxy. In any case, you can enable the option by creating (or editing) /etc/docker/ daemon.json to have: run: /sbin/sysctl net.ipv4.conf.docker0.route_localnet=1 in the Dockerfile or your scripts, to pass down a port number (and address) to bind to. By default, when you create a container, it does not publish any of its ports to the outside world. To make a port available to services outside of Docker, or to Docker containers which are not connected to the container’s network, use the --publish or -p flag. This creates a firewall rule which maps a container port to a port on the Docker host.

Comments
  • What command did you use to start the container? Also post the output of docker ps when the container is running.
  • Can you confirm sshd is actually running on the container? Run docker exec -ti 201bde6c839a /bin/bash, once you are in, post the output of ps aux and netstat -taln
  • In my Docker host, all docker ports are listening on IPv6 and have no problem connecting to ssh on containers.
  • @Danielt. i have added the info. I am able ssh using exec but i am not able to ssh into container directly from outside using host port 40122 from mac
  • You could hitting this issue github.com/docker/docker/issues/2174 , i am not sure if it is resolved. Can you also share how you are trying to connect through ssh and the error you are getting?
  • This is a big problem actually. Public cloud like Azure, doesnt speak IPV6 very well, for instance the public Azure load-balancer is attempting an IPV4 as backend.
  • Seems you may need to install the "Docker VM Extension" in Azure and use Ubuntu 14.04 LTS. However, I do not think there is an issue with ipv6 as this is only on the local host, not the network.
  • You are right, the issue was in my config (disabling IPV6 is not a good idea ^^)
  • @bigdong you want ipv6 on.
  • @Michael You are my timesaver. :)
  • This answer has one advantage: it allows you to "fix" the issue without having to restart the docker daemon (the answer with changing docker config below does). Regarding the top, selected answer: I actually had sysctl net.ipv6.bindv6only=0 so changing this config did not help.
  • does this work on debian ? shouldn't it be /etc/default/docker ?
  • @BigDong thanks for the comment, I'm on RedHat like OS so the path is a little different from one OS to the other I tried to reflect your comment in the answer