docker ports not available - spring-boot

I have a spring-config-sever project that I am trying to run via Docker. I can run it from the command line and my other services and browser successfully connect via:
http://localhost:8980/aservice/dev
However, if I run it via Docker, the call fails.
My config-server has a Dockerfile:
FROM openjdk:8-jdk-alpine
VOLUME /tmp
ARG JAR_FILE=build/libs/my-config-server-0.1.0.jar
ADD ${JAR_FILE} my-config-server-0.1.0.jar
EXPOSE 8980
ENTRYPOINT ["java","-Djava.security.egd=file:/dev/./urandom","-jar","/my-config-server-0.1.0.jar"]
I build via:
docker build -t my-config-server .
I am running it via:
docker run my-config-server -p 8980:8980
And then I confirm it is running via
docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
1cecafdf99fe my-config-server "java -Djava.securit…" 14 seconds ago Up 13 seconds 8980/tcp suspicious_brahmagupta
When I run it via Docker, the browse fails with a "ERR_CONNECTION_REFUSED" and my calling services fails with:
Could not locate PropertySource: I/O error on GET request for
"http://localhost:8980/aservice/dev": Connection refused (Connection
refused);

Adding full answer based on comments.
First, you have to specify -p before image name.
docker run -p 8980:8980 my-config-server.
Second, just configuring localhost with host port won't make your my-service container to talk to other container. locahost in container is within itself(not host). You will need to use appropriate docker networking model so both containers can talk to each other.
If you are on Linux, the default is Bridge so you can configure my-config-server container ip docker inspect {containerIp-of-config-server} as your config server endpoint.
Example if your my-config-server ip is 172.17.0.2 then endpoint is - http://172.17.0.2:8980/
spring:
cloud:
config:
uri: http://172.17.0.2:8980
Just follow the docker documentation for little bit more understanding on how networking works.
https://docs.docker.com/network/network-tutorial-standalone/
https://docs.docker.com/v17.09/engine/userguide/networking/
If you want to spin up both containers using docker-compose, then you can link both containers using service name. Just follow Networking in Compose.

I could imagine that the application only listens on localhost, ie 127.0.0.1.
You might want to try setting the property server.address to 0.0.0.0.
Then port 8980 should also be available externally.

Related

Docker hub jhipster-registry not accessible on port 8761

I have recently started exploring the microservice architecture using jhipster and was trying to install and run the jhipster-registry from docker hub. Docker shows that the registry is running, but I am unable to access it on port 8761.
Pulled the image with docker pull jhipster/jhipster-registry
Started the container with docker run --name jhipster-registry -d jhipster/jhipster-registry
Here's a snapshot of what docker container ls returns:
Am I missing something over here?
You are starting the JHipster Registry container, but you aren't exposing the port.
You can expose a port by passing the port flag -p 8761:8761 which will enable you to connect to it via localhost:8761 or 127.0.0.1:8761 in a browser.
You may need to configure some environment variables for the JHipster Registry to start correctly. These may depend on your generated app's options, such as authentication type. For convenience JHipster apps come with a docker-compose.yml file. You can start it with docker-compose -f src/main/docker/jhipster-registry.yml up, as documented.

docker image running not able to access api in spring boot gradle

I have created a image of spring boot gradle project by using command gradlew jibDockerBuild
I run the image by this command docker run -p 8082:8082 demo:0.0.1-SNAPSHOT.Image is running successfully on port 8082.In project application.properties server.port is 8082 only.
I am not able accesss api so I have checked in my machine whether this process is running on the port or not by command netstat -a -n -o | find "8082".No process is running on that port.
When you install Docker on Windows by Docker Toolbox by default Docker will run on 192.168.99.100 IP (DOCKER_IP).
You can access all your containers running inside docker with DOCKER_IP on your Host machine ie Windows.
Read more on it here
Regarding your mapping query
You have mapped port, which means your container port will be mapped to DOCKER_IP:PORT
If you were using Docker on Linux or Mac it will get mapped to localhost:port as in those cases Docker is running on localhost.
The same is not true for Windows at least with Docker Toolbox.
As per your configuration, you can access your application on HOST machine by hitting
http://192.168.99.100:8082

How to visit a docker service by ip address

I'm new with docker and I'm probably missing a lot, although i went through the basic documentation and I'm trying to deploy a simple Spring Boot API
I've deployed my API as a docker-spring-boot .jar file , then i installed docker and pushed it with the following commands:
sudo docker login
sudo docker tag docker-spring-boot phillalexakis/myfirstapi:01
sudo docker push phillalexakis/myfirstapi:01
Then i started the API with the docker run command:
sudo docker run -p 7777:8085 phillalexakis/myfirstapi:01
When i visit localhost:7777/hello I'm getting the desired response
This is my Dockerfile
FROM openjdk:8
ADD target/docker-spring-boot.jar docker-spring-boot.jar
EXPOSE 8085
ENTRYPOINT ["java","-jar","docker-spring-boot.jar"]
Based on this answered post this the command to get the ip address
docker inspect -f '{{range .NetworkSettings.Networks}}{{.IPAddress}}{{end}}' container_name_or_id
So, i run it with container_name_or_id = phillalexakis/myfirstapi:01 and I'm getting this error
Template parsing error: template: :1:24: executing "" at <.NetworkSettings.Networks>: map has no entry for key "NetworkSettings"
If i manage somehow to get the IP will i be able to visit it and get the same response?
This is how i have it in my mind: ip:7777/hello
You have used the image name and not the container name.
Get the container name by executing docker ps.
The container ID is the value in the first column, the container name is the value in the last column. You can use both.
Then, when you have the IP, you will be able to access your API at IP:8085/hello, not IP:7777/hello
The port 7777 is available on the Docker Host and maps to the port 8085 on the container. If you are accessing the container directly - which you do, when you use its IP address - you need to use the port that the container exposes.
There is also another alternative:
You can give the container a name when you start it by specifying the --name parameter:
sudo docker run -p 7777:8085 --name spring_api phillalexakis/myfirstapi:01
Now, from your Docker host, you can access your API by using that name: spring_api:8085/hello
You should never need to look up that IP address, and it often isn't useful.
If you're trying to call the service from outside Docker space, you've done the right thing: use the docker run -p option to publish its port to the host, and use the name of the host to access it. If you're trying to call it from another container, create a network, make sure to run both containers with a --net option pointing at that network, and they can reach other using the other's --name as a hostname, and the container-internal port the other service is listening on (-p options have no effect and aren't required).
The Docker-internal IP address just doesn't work in a variety of common situations. If you're on a different host, it will be unreachable. If your local Docker setup uses a virtual machine (Docker Machine, Docker for Mac, minikube, ...) you can't reach the IP address directly from the host. Even if it does work, when you delete and recreate the container, it's likely to change. Looking it up as you note also requires an additional (privileged) operation, which the docker run -p path avoids.
The invocation you have matches the docker inspect documentation (as #DanielHilgarth notes, make sure to run it on the container and not the image). In the specific situation where it will work (you are on the same native-Linux host as the container) you will need to use the unmapped port, e.g. http://172.17.0.2:8085/hello.

Docker on Mac is running but refusing to expose port

Mac here, running Docker Community Edition Version 17.12.0-ce-mac49 (21995).
I have Dockerized a web app with a Dockerfile like so:
FROM openjdk:8
RUN mkdir /opt/myapp
ADD build/libs/myapp.jar /opt/myapp
ADD application.yml /opt/myapp
ADD logback.groovy /opt/myapp
WORKDIR /opt/myapp
EXPOSE 9200
ENTRYPOINT ["java", "-Dspring.config=.", "-jar", "myapp.jar"]
I then build that image like so:
docker build -t myapp .
I then run a container of that image like so:
docker run -it -p 9200:9200 --net="host" --env-file ~/myapp-local.env --name myapp myapp
In the console I see the app start up without any errors, and all seems to be well. Even my metrics publishes (which publish heartbeat and other health metrics every 20 seconds) are printing to the console as I would expect them to. Everything seems to be fine.
Except when I go to run a curl against my app from another terminal/session:
curl -i -H "Content-Type: application/json" -X POST -d '{"username":"heyitsme","password":"12345"}' http://localhost:9200/v1/auth/signIn
curl: (7) Failed to connect to localhost port 9200: Connection refused
Now, if this were a situation where the /v1/auth/signIn path wasn't valid, or if there was something wrong with my request entity/payload, the server would pick up on it and send an error (I assure you; as I can confirm this exact same curl works when I run the server outside of Docker as just a standalone service).
So this is definitely a situation where the curl command can't connect to localhost:9200. Again, when I run my app outside of Docker, that same curl command works perfectly, so I know my app is trying to standup on port 9200.
Any ideas as to what could be going wrong here, or how I could begin troubleshooting?
The way you run your container has 2 conflicting parts:
-p 9200:9200 says: "publish (bind) port 9200 of the container to port 9200 of the host"
--net="host" says: "use the host's networking stack"
According to Docker for Mac - Networking docs / Known limitations, use cases, and workarounds, you should only publish a port:
I want to connect to a container from the Mac
Port forwarding works for localhost; --publish, -p, or -P all work. Ports exposed from Linux are forwarded to the Mac.
Our current recommendation is to publish a port, or to connect from another container. This is what you need to do even on Linux if the container is on an overlay network, not a bridge network, as these are not routed.
The command to run the nginx webserver shown in Getting Started is an example of this.
$ docker run -d -p 80:80 --name webserver nginx
Check that your app bind to 0.0.0.0:9200 and not localhost:9200 or something similar
Problem seems to be in the network mode you are running the container.
Quick test: Login to your container and run the curl cmd there, hopefully it works. That would isolate the problem to request not being forwarded from host to container.
Try running your container on the default bridge network and test.
Refer to this blog for details on the network modes in docker
TLDR; You will need to add an IPtables entry to allow the traffic to enter your container.

How to access webserver running on localhost from a docker container on a network?

I have the following system configuration:
Docker container running on user defined network
docker-machine (with VirtualBox on OS:X forwarding port 9000 to 9000)
Local webserver running on http://localhost:9000
I do not know how to make a basic http request against this webserver, from within my docker container.
To test this I am using:
docker exec testcontainer curl --data "foobaz=foo" http://{hostname}:9000/
where I have tried, for hostnames:
'localhost'
'127.0.0.1'
'192.168.99.100' (docker-machine IP)
Each time I receive errors or timeouts. When I run the curl command locally (not in docker and on my host OS:X machine) I am able to successfully post the http request.
I cannot disconnect the docker container from my user-defined network. I also cannot add my webserver to that network, as it is not running in a container. Also, I know it is trivial to connect the other way (curl to a webserver running in a docker container) but this is not my use case.
How can I successfully route that http request from the docker container which is part of a user defined network to my localhost webserver?
You can do this with the actual IP address of your local computer.
So for example, if your en0 IP is 10.100.20.32 on your host OS, you can run:
docker exec testcontainer curl --data "foobaz=foo" http://10.100.20.32:9000/
which will successfully allow you to make the http requests.
Note that if you are doing this from a container on the host docker network, this is trivial, as you can directly access localhost or 0.0.0.0 without having to use the actual machine IP.
You might want to check what the IP address of the container is - you can find this out by running docker inspect.
However, if you want to access the server process running in your container using the docker machine IP, then you should "expose" port 9000 that your contained app is listening on (using Dockerfile) - in this way, you will still need to figure out which port the 9000 container port is mapped to (this shows when you list your containers via $ docker ps. You can also specify port binding option in command line when starting your container like this: $ docker run -p 9000:9000 <your-container>.

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