I'im fairly new to docker and docker compose.
I have a simple scenario, based on three applications (app1, app2, app3) that I want to connect to my host's network. The purpose is having an internet connection also inside the container.
Here is my docker-compose file:
version: '3.9'
services:
app1container:
image: app1img
build: ./app1
networks:
network_comp:
ipv4_address: 192.168.1.1
extra_hosts:
anotherpc: 192.168.1.44
ports:
- 80:80
- 8080:8080
app2container:
depends_on:
- "app1container"
image: app2img
build: ./app2
networks:
network_comp:
ipv4_address: 192.168.1.2
ports:
- 3100:3100
app3container:
depends_on:
- "app1container"
image: app3img
build: ./app3
networks:
network_comp:
ipv4_address: 192.168.1.3
ports:
- 9080:9080
networks:
network_comp:
driver: ""
ipam:
driver: ""
config:
- subnet: 192.168.0.0/24
gateway: 192.168.1.254
I already read the docker-compose documentation, which says that there is no a bridge driver for Windows OS. Is there anyway a solution to this issue?
You shouldn't usually need to do any special setup for this to work. When your Compose service has ports:, that makes a port available on the host's IP address. The essential rules for this are:
The service inside the container must listen on the special 0.0.0.0 "all interfaces" address (not 127.0.0.1 "this container only"), on some (usually fixed) port.
The container must be started with Compose ports: (or docker run -p). You choose the first port number, the second port number must match the port inside the container.
The service can be reached via the host's IP address on the first port number (or, if you're using the older Docker Toolbox setup, on the docker-machine ip address).
http://host.example.com:12345 (from other hosts)
|
v
ports: ['12345:8080'] (in the `docker-compose.yml`)
|
v
./my_server -bind 0.0.0.0:8080 (the main container command)
You can remove all of the manual networks: configuration in this file. In particular, it's problematic if you try to specify the Docker network to have the same IP address range as the host network, since these are two separate networks. Compose automatically provides a network named default that should work for most practical applications.
Related
how can we run docker commands inside container with docker-compose?
Simply I want to get IP of some other network container.
I am running three container va-server, db and api-server. All the containers are in same docker-network
Here I am providing docker-compose file below:
version: "2.3"
services:
va-server:
container_name: va_server
image: nitinroxx/facesense:amd64_2022.11.28 #facesense:alpha
runtime: nvidia
restart: always
mem_limit: 4G
networks:
- perimeter-network
db:
container_name: mongodb
image: mongo:latest
ports:
- "27017:27017"
restart: always
volumes:
- ./facesense_db:/data/db
command: [--auth]
networks:
- perimeter-network
api-server:
container_name: api_server
image: nitinroxx/facesense:api_amd64_2022.11.28
ports:
- "80:80"
- "465:465"
restart: always
networks:
- perimeter-network
networks:
perimeter-network:
driver: bridge
ipam:
config:
- gateway: 10.16.239.1
subnet: 10.16.239.0/24
I have install docker inside the container which giving me below permission error:
docker.errors.dockerexception: error while fetching server api version: ('connection aborted.', permissionerror(13, 'permission denied')
...inside [a] container [...] I want to get IP of some other network container....
Docker provides an internal DNS service that can resolve container names to their Docker-internal IP addresses. From one of the containers you show, you could look up a host name like db to get the container's IP address; but in practice, this is a totally normal DNS name and all but the lowest-level networking interfaces can use those directly.
This does require that all of the containers involved be on the same Docker network. Normally Compose sets this up automatically for you; in the file you show I might delete the networks: blocks and container_name: overrides in the name of simplicity. Also see Networking in Compose in the Docker documentation.
In short:
You can probably use the Compose service names va-server, db, and api-server as host names without specifically knowing their IP addresses.
This probably means you never need to know the container IP addresses at all (they're usually unusable from outside Docker).
If you do need an IP address from inside a container, a DNS lookup can find it.
You can't usually run docker commands from inside containers. You can't do this safely without making it possible for the container to take over the whole host. There are usually better patterns that don't tie you to the Docker stack specifically.
I want to ask a static IP within the docker container.
I can assign an IP address if there is the IPAM configuration in the network.
version: "2.1"
services:
nginx:
image: ghcr.io/linuxserver/nginx
container_name: nginx
volumes:
- ./config:/config
ports:
- 443:443
restart: always
networks:
br-uplink:
ipv4_address: 192.168.1.2
networks:
br-uplink:
driver: bridge
name: br-uplink
ipam:
config:
- subnet: "192.168.1.0/24"
gateway: "192.168.1.1"
but if there is no IPAM, then this does not work.
$ docker compose up -d
[+] Running 1/2
⠿ Network br-uplink Created
⠋ Container nginx Creating
Error response from daemon: user specified IP address is supported only when connecting to networks with user configured subnets
So if I remove ipv4_address and IPAM configuration, then a random address is assigned.
and if I assign manually within the container, it works.
docker compose exec nginx bash
ip add flush dev eth0
ip add add 192.168.11.2/24 dev eth0
How can I make this possible automatically?
I don't want to create my own Dockerfile for this, it would be happy if this can be done within the docker-compose.yml.
Any ideas?
I have started learning about Docker and containers, and have been given an assignment to "Host a docker container on the external network (the one that the host is connected to) with its own IP address that is valid for said network".
As far as my understanding goes, Docker containers allow to forward ports onto the host, without exposing the docker container to the outside network. Is there any way to expose the whole container, with all its ports and have its own IP onto the external network?
Here is a excerpt from a test docker-compose.yaml file:
env20:
build: ./env20
image: env20
container_name: env20
hostname: env20
ports:
- "22:22/tcp"
- "80:80/tcp"
depends_on:
- mysql
networks:
gnet:
ipv4_address: 10.10.11.30
restart: unless-stopped
#############################################################
# Netowrk setup
#############################################################
networks:
gnet:
name: gnet
driver: macvlan
ipam:
driver: default
config:
- subnet: 10.10.11.0/24
gateway: 10.10.11.1
Any help would be appreciated!
Hi everyone i have create a network with mac-vlan type in docker because i wanted my containers to be on the same LAN as host.Now the strange thing which i have noticed is that when i stop and then restart a container with docker start command the container gets started but the IP assigned to it is the one that was assigned before the container was shutdown. doesn't IP change when containers are restarted furthermore the container is now not reachable because the IP its showing as its own has now been reassigned to another machine on the network from what i have read that the container is assigned the same IP as before but if the container couldn't get the IP it fails to start but my container is starting just fine. What am i missing here? on ubuntu version 17.10 docker version 17.11.0-ce Api version 1.34 (both client and server)
You should not use static IP's in docker unless you are working with something that allows routing from outside to the inside container, like in you're case macvlan. DNS is already there for service discovery inside of the container network and supports container scaling. And outside the container network, you should use exposed ports on the host.
That being said, you can achieve the above using docker-compose like below :
services:
mysql:
container_name: backend-database
image: mysql:latest
restart: always
environment:
- MYSQL_ROOT_PASSWORD=root
ports:
- "3306:3306"
networks:
mynetwork:
ipv4_address: 10.5.0.5
apache-tomcat:
container_name: apache-tomcat
build: tomcat/.
ports:
- "8080:8080"
- "8009:8009"
networks:
mynetwork:
ipv4_address: 10.5.0.6
depends_on:
- mysql
networks:
mynetwork:
driver: bridge
ipam:
config:
- subnet: 10.5.0.0/16
gateway: 10.5.0.1
I have a docker-compose file which is globally like this.
version '2'
services:
app:
image: myimage
ports:
- "80:80"
networks:
mynet:
ipv4_adress: 192.168.22.22
db:
image: postgres:9.5
ports:
- "6432:5432"
networks:
mynet:
ipv4_adress: 192.168.22.23
...
networks:
mynet:
driver: bridge
ipam:
driver: default
config:
- subnet: 192.168.22.0/24
I want to put my postgresql and application in subnetworks to avoid the ports to be exposed outside my computer/server.
From within the app container, I can't connect to 192.168.22.23, I installed net-tools to use ifconfig/netstat, and it doesn't seem the containers are able to communicate.
I assume I have this problem because I'm using subnetworks with static ipv4 adresses.
I can access both static IPs from the host (connect to postgres and access the application)
Do you have any piece of advice, the goal is to access the ports of another container to communicate with him, without removing the use of static ips (on app at least). Here, to connect to postgresql from the app container.
The docker run -p option and Docker Compose ports: option take a bind address as an optional parameter. You can use this to make a service accessible from the same host, but not from other hosts:
services:
db:
ports:
- '127.0.0.1:6432:5432'
(The other good use of this setting is if you have a gateway machine with both a public and private network interface, and you want a service to only be accessible from the private network.)
Once you have this, you can dispense with all of the manual networks: setup. Non-Docker services on the same host can reach the service via the special host name localhost and the published port number. Docker services can use inter-container networking; within the same docker-compose.yml file you can use the service name as a host name, and the internal port number.
host$ PGHOST=localhost PGPORT=6432 psql
services:
app:
environment:
- PGHOST=db
- PGPORT=5432
You should remove all of the manual networks: setup, and in general try not to think about the Docker-internal IP addresses at all. If your Docker is Docker for Mac or Docker Toolbox, you cannot reach the internal IP addresses at all. In a multi-host environment they will be similarly unreachable from hosts other than where the container itself is running.