What is IP of bridge localhost for Docker? - docker

Question

I am dockerizing my application. I have two containers now. One of it wants to talk to another, in it's config I have "mongo": "127.0.0.1" I suppose they should talk through the bridge network:
$ docker network inspect bridge
[
{
"Name": "bridge",
"Id": "f7ab26d71dbd6f557852c7156ae0574bbf62c42f539b50c8ebde0f728a253b6f",
"Scope": "local",
"Driver": "bridge",
"IPAM": {
"Driver": "default",
"Config": [
{
"Subnet": "172.17.0.1/16",
"Gateway": "172.17.0.1"
}
]
},
"Containers": {},
"Options": {
"com.docker.network.bridge.default_bridge": "true",
"com.docker.network.bridge.enable_icc": "true",
"com.docker.network.bridge.enable_ip_masquerade": "true",
"com.docker.network.bridge.host_binding_ipv4": "0.0.0.0",
"com.docker.network.bridge.name": "docker0",
"com.docker.network.driver.mtu": "9001"
},
"Labels": {}
}
]
Should I now change "mongo": "127.0.0.1" to "mongo": "0.0.0.0"?

Answer 1

You can check a container IP.
$ docker inspect $(container_name) -f "{{json .NetworkSettings.Networks}}"
You can find IPAddress attribute from the output of json.

Answer 2

Yes, you should use a bridge network. The default "bridge" can be used but won't give you DNS resolution, check https://docs.docker.com/engine/userguide/networking/#user-defined-networks for details.

Answer 3

Best way to use is using with --link option to avoid to many changes.
for ex: --link mongo01:mongo it will instruct Docker to use the container named mongo01 as a linked container, and name it mongo inside your application container
So in your application you can use mongo:27017. without making any changes.
refer this for more details.
https://www.thachmai.info/2015/05/10/docker-container-linking-mongo-node/