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3rd chunk of `content/manuals/engine/network/drivers/bridge.md`
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| `com.docker.network.bridge.enable_ip_masquerade`                                                | `true`                      | Enable IP masquerading.                                                                             |
| `com.docker.network.bridge.gateway_mode_ipv4`<br/>`com.docker.network.bridge.gateway_mode_ipv6` | `nat`                       | Control external connectivity. See [Packet filtering and firewalls](packet-filtering-firewalls.md). |
| `com.docker.network.bridge.enable_icc`                                                          | `true`                      | Enable or Disable inter-container connectivity.                                                     |
| `com.docker.network.bridge.host_binding_ipv4`                                                   | all IPv4 and IPv6 addresses | Default IP when binding container ports.                                                            |
| `com.docker.network.driver.mtu`                                                                 | `0` (no limit)              | Set the containers network Maximum Transmission Unit (MTU).                                         |
| `com.docker.network.container_iface_prefix`                                                     | `eth`                       | Set a custom prefix for container interfaces.                                                       |
| `com.docker.network.bridge.inhibit_ipv4`                                                        | `false`                     | Prevent Docker from [assigning an IP address](#skip-bridge-ip-address-configuration) to the bridge. |

Some of these options are also available as flags to the `dockerd` CLI, and you
can use them to configure the default `docker0` bridge when starting the Docker
daemon. The following table shows which options have equivalent flags in the
`dockerd` CLI.

| Option                                           | Flag        |
| ------------------------------------------------ | ----------- |
| `com.docker.network.bridge.name`                 | -           |
| `com.docker.network.bridge.enable_ip_masquerade` | `--ip-masq` |
| `com.docker.network.bridge.enable_icc`           | `--icc`     |
| `com.docker.network.bridge.host_binding_ipv4`    | `--ip`      |
| `com.docker.network.driver.mtu`                  | `--mtu`     |
| `com.docker.network.container_iface_prefix`      | -           |

The Docker daemon supports a `--bridge` flag, which you can use to define
your own `docker0` bridge. Use this option if you want to run multiple daemon
instances on the same host. For details, see
[Run multiple daemons](/reference/cli/dockerd.md#run-multiple-daemons).

### Default host binding address

When no host address is given in port publishing options like `-p 80`
or `-p 8080:80`, the default is to make the container's port 80 available on all
host addresses, IPv4 and IPv6.

The bridge network driver option `com.docker.network.bridge.host_binding_ipv4`
can be used to modify the default address for published ports.

Despite the option's name, it is possible to specify an IPv6 address.

When the default binding address is an address assigned to a specific interface,
the container's port will only be accessible via that address.

Setting the default binding address to `::` means published ports will only be
available on the host's IPv6 addresses. However, setting it to `0.0.0.0` means it
will be available on the host's IPv4 and IPv6 addresses.

To restrict a published port to IPv4 only, the address must be included in the
container's publishing options. For example, `-p 0.0.0.0:8080:80`.

## Manage a user-defined bridge

Use the `docker network create` command to create a user-defined bridge
network.

```console
$ docker network create my-net
```

You can specify the subnet, the IP address range, the gateway, and other
options. See the
[docker network create](/reference/cli/docker/network/create.md#specify-advanced-options)
reference or the output of `docker network create --help` for details.
Title: User-Defined Bridge Network Options and Management
Summary
This section outlines further options for configuring user-defined bridge networks in Docker, including IP masquerading, gateway mode, inter-container connectivity, host binding IP, MTU, and interface prefix. It also notes the equivalent `dockerd` CLI flags for some options. Furthermore, it details how to manage the default host binding address for published ports. Finally, it shows how to create a user-defined bridge using `docker network create` and refers to its documentation for advanced options like subnet, IP range, and gateway configuration.