I run docker with my private eth0m interface as explained here
I want to run docker without docker0 and 172.... interface
how to disable docker0?
Why would you remove docker0 ?
When Docker starts, it creates a virtual interface named docker0 on the host machine.
[...]
But docker0 is no ordinary interface. It is a virtual Ethernet bridge that automatically forwards packets between any other network interfaces that are attached to it. This lets containers communicate both with the host machine and with each other.
source:
https://docs.docker.com/articles/networking/
You need some bridge to run docker.
If you have another bridge for this, just delete default docker0.
Solution found.
First I configure my bridge0 via init scripts or NetworkManager,then
edit /etc/docker/daemon.json
{
"bridge": "bridge0"
}
Related
Everytime I try to start any container in bridged network mode, the virtual network adapter is not added to the docker0 bridge. As a result, these containers don't have access to the network. I see the docker0 bridge and vethXXXXXX#ifXXX virtual interface from ip addr. However, brctl show shows the docker0 bridge with no interface attached. I can manually add the interface using brctl addif vethXXXXXX docker0 and everything works fine.
Some containers exit so quickly due to the connection problem that I don't have a chance to add them before they get a new virtual interface when restarting.
I already deleted all the docker network adapter and let them reinitialize by restarting docker, without success.
Does anybody know how I can fix this, so that network interfaces of container get automatically added to the docker0 bridge on startup?
Thanks
You can use networkctl to check veth status.
networkctl status -a
It might match incorrect network setting. You can use another higher priority systemd-networkd setting to correct it.
ex:
Create a new file /etc/systemd/network/20-docker-veth.network
with content
[Match]
Name=veth*
Driver=veth
[Link]
Unmanaged=true
and restart the systemd-networkd service.
sudo systemctl restart systemd-networkd.service
Then, start a new container with bridge network would auto link to veth.
ref: https://forums.docker.com/t/archlinux-container-veth-interfaces-being-assigned-to-wrong-bridge/107197/2
I have linux machine, with docker installed, that works also as NAT router. It has multiple interfaces and I need docker to communicate by default with only one of them. After hours of trying custom networks, the best solution I found is to set the interface IP when specifying port mappings:
docker run -p 192.168.0.1:80:80 -d nginx
Where 192.168.0.1 is my interface IP. Is it possible to set docker to use that IP (interface) every time? E.g. when I download someone's docker-compose.yml and use it without changes.
you can add the "ip" option to /etc/docker/daemon.json:
{
[...]
"ip":"192.168.0.1"
}
After restarting the service, ports will be exposed on this interface instead of default 0.0.0.0 one.
afaik, the daemon.json file can accept any options as defined on dockerd itself: https://docs.docker.com/engine/reference/commandline/dockerd/
I have a server with several virtual machines running. I am starting a container with Jira installation and i need the container to be assigned with different address from the DHCP and not use the host IP address. I am a noobie so please explain
The technique suggested in #ad22's answer requires a custom build of the Docker engine that uses a fork of libnetwork. Now, more than four years after that hack was developed, the DHCP feature has still not been merged into the standard Docker engine, and the fork has fallen far behind the mainline code.
Since late 2019, it has been possible to assign IP addresses to Docker containers with DHCP using devplayer0's docker-net-dhcp plugin, which works with the standard Docker engine. When you create a new container, this plugin starts a Busybox udhcpc client to obtain a DHCP lease, then runs udhcpc (in a process outside the container's PID namespace) to renew the lease as needed.
As found in the other answer, using the macvlan will not enable the container to obtain addresses from DHCP. The functionality to obtain addresses from DHCP is experimental (this was created by someone associated with the docker libnetwork project)
https://gist.github.com/nerdalert/3d2b891d41e0fa8d688c
It suggests compiling the changes into the docker binary and then running
docker network create -d macvlan \
--ipam-driver=dhcp \
-o parent=eth0 \
--ipam-opt dhcp_interface=eth0 mcv0
Since this requires re-compiling the binary, an alternate solution could be to
assign static IP addresses to all your containers using the "--ip" option to docker run/compose, and get a DNS entry for your hostname assigned to this IP, and also ensure that the IP can never be assigned through DHCP.
You can achieve this using the docker network macvlan driver. According to the docs:
...you can use the macvlan network driver to assign a MAC address to each container’s virtual network interface, making it appear to be a physical network interface directly connected to the physical network.
So essentially, the virtual network interface will use the physical network interface exposed on the host to advertise its own virtual MAC address. This will then be broadcast to the LAN on which the DHCP server is operating, and the virtual interface will be assigned an IP.
The steps to get it going are:
Create a docker network which uses the macvlan driver:
docker network create \
--driver macvlan \
--subnet=172.16.86.0/24 \
--gateway=172.16.86.1 \
--opt parent=eth0 lan_net
The subnet and gateway would be those of your LAN network (on which the DHCP resides). The parent option specifies the physical interface on the host through which you would like your virtual interface to be exposed to the LAN network.
Run your container using the newly created network:
docker run -it --rm --net=lan_net alpine
I would like to remove the interface docker0. It would be better to avoid creating the interface docker0 when starting the service and using directly the eth0.
To delete the interface, use:
ip link delete docker0
You may require sudo privilege.
By default, the Docker server creates and configures the host system’s docker0 interface as an Ethernet bridge inside the Linux kernel that can pass packets back and forth between other physical or virtual network interfaces so that they behave as a single Ethernet network.
Look at Understand Docker container networks and Customize the docker0 bridge
When you install Docker, it creates three networks automatically. You can list these networks using the docker network ls command:
$ docker network ls
Historically, these three networks (bridge, none, host) are part of Docker’s implementation. When you run a container you can use the --network flag to specify which network you want to run a container on. These three networks are still available to you.
The bridge network represents the docker0 network present in all Docker installations. Unless you specify otherwise with the docker run --network= option, the Docker daemon connects containers to this network by default. You can see this bridge as part of a host’s network stack by using the ifconfig command on the host.
I support #gile's solution.
Be careful when removing interfaces. I do not recommend you to remove bridge docker0 (the default docker0 is as a bridge - in my case).
The documentation says:
Bridge networks are usually used when you are in standalone containers
that need to communicate.
https://docs.docker.com/network/#network-drivers
If you want to remove this interface, you can use the following tools in addition to the above solutions (for removing / adding interfaces I suggest you use the tools provided with the docker):
nmcli connection delete docker0
docker network rm docker0
brctl delbr docker0
If you don't want to create docker0 interface at all when docker starts then edit daemon.json(which is configuration file for docker) file to add line "bridge": "none" line to that json.
I have trouble with connecting to VPN after installing docker. The solution would be the following:
You can see the ip route table by executing ip route command in linux. Then delete any domains start with 172.16.x.x.
For example:
> ip route
default via 192.168.1.1 dev wlp2s0 proto dhcp metric 20600
169.254.0.0/16 dev wlp2s0 scope link metric 1000
172.16.14.0/24 dev vmnet8 proto kernel scope link src 172.16.14.1
172.16.57.0/24 dev vmnet1 proto kernel scope link src 172.16.57.1
192.168.1.0/24 dev wlp2s0 proto kernel scope link src 192.168.1.4 metric 600
Then delete them like the following:
sudo ip route del 172.16.14.0/24 dev vmnet8 proto kernel scope link src 172.16.14.1
sudo ip route del 172.16.57.0/24 dev vmnet1 proto kernel scope link src 172.16.57.1
I have a docker instance on a host which has two network interfaces, one attached to the internet and one virtual private network.
The host is able to connect to the internet and the VPN.
The docker instance running on the host can connect to the internet, but cannot reach the VPN.
How can I assure my docker instance can connect to the VPN?
I have read explanation about using pipework (https://github.com/jpetazzo/pipework/) but don't see how I can get this to work for me.
I am using docker 0.8.0 on Ubuntu 13.10.
Thanks for the help.
I think that you do not need pipework. In default configuration, you should be able to reach both host interfaces from docker eth0 interface. Possible problems:
DNS: my default container resolv.conf is 8.8.8.8 and it may not know some VPN-specific domain names.
Filtering/firewall at host possibly drops/does not forward packets to VPN. (check firewall f.e ufw status, ...)
You can check IP ranges for possible conflicts in docker networking. In case of conflict, you can configure docker network interface docker0 manually to be ok with your VPN:
/etc/network/interfaces:
auto docker0
iface docker0 inet static
address 192.168.1.1 <--- configure this
netmask 255.255.255.0
bridge_stp off
bridge_fd 0