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Build application on docker

I build web application and service to docker from tomcat directory, in web application application.properties file I specify service url with port 8886 but when i use web call to api the application is calling on port 886. Please help me!!
I tried changing other ports, changing environment variable name but same result

Cannot override properties in Hazelcast.yaml for Spring Boot Application

I have Spring Boot application with Hazelcast (use 4.2 and also try to use 4.0.3 of hazelcast-all dependency). Hazelcast is configured for embedded topology. I use TCP-IP network join way. Properties for Hazelcast are set using file Hazelcast.yaml and Spring Boot property: spring.hazelcast.config (Spring by default use this name for Hazelcast config, it is redundant).
In property member-list I indicate IP addresses of two machines in one subnet (e.g. 192.0.0.1 and 192.0.0.2).
I build application in Docker using image based on Alpine on OpenJdk. Image includes start java -jar command as ENTRYPOINT.
PROBLEM PREMISE:
I run two docker containers on two machines described earlier. I forward only port 5701 (using -p) on both containers. And containers don't see each other. Spring Boot logs show that the container network is being used.
PS:
All work if run docker with --net host.
Also all work if I package Spring Boot application with property public-address in Hazelcast.yaml for two containers - once package with value 192.0.0.1, the other with value 192.0.0.2. Spring Boot Hazelcast instances see each other using network of machine (192.0.0.1 and 192.0.0.2).
PROBLEM:
I try to override property public-address in Hazelcast.yaml using:
docker run -e HZ_NETWORK_PUBLICADDRESS=192.0.0.1
export HZ_NETWORK_PUBLICADDRESS=192.0.0.1 && docker run
JAVA_OPTS="-Dhz.network.public-address=192.0.0.1"
JAVA_OPTS="-Dhazelcast.local.publicAddress=192.0.0.1"
JAVA_OPTS="-Dhazelcast.config=/mnt/overrided_hazelcast.yaml"
ENV HZ_NETWORK_PUBLICADDRESS=192.0.0.1 - in Dockerfile
ENTRYPOINT java -jar -Dhz.network.public-address=192.0.0.1 my-app.jar
Nothing works. Does anyone know why it is not possible to override property public-address in the Hazelcast.yaml at startup?
Or maybe anyone knows how I can run two Spring Boot applications with embedded Hazelcast in separate Docker containers on separate machines.

The way you set up Hazelcast public address is correct, at least starting from Hazelcast 4.1 where the Config Override feature was added.
To check the working version, you can have a look at Hazelcast Guide: Embedded Hazelcast on Kubernetes. Instead of Hazelcast Kubernetes configuration, you can use TCP-IP. The following Hazelcast configuration worked for me (my host IP is 172.22.41.210).
hazelcast:
cluster-name: hazelcast-cluster
network:
join:
tcp-ip:
enabled: true
member-list:
- 172.22.41.210:5701
- 172.22.41.210:5702
Then, building and starting two applications should form a cluster.
$ mvn package && docker build -t hazelcast-embedded .
$ docker run --rm -e HZ_NETWORK_PUBLICADDRESS=172.22.41.210 -p 5701:5701 hazelcast-embedded
$ docker run --rm -e HZ_NETWORK_PUBLICADDRESS=172.22.41.210:5702 -p 5702:5701 hazelcast-embedded
You should see that the cluster was formed in the application logs.
Members {size:2, ver:2} [
Member [172.22.41.210]:5701 - 21af9e1a-7e98-4305-905c-451ee23486c3 this
Member [172.22.41.210]:5702 - 0507d970-1f31-4df3-9ea5-8c3981eb7c98
]

Why does java app started in Docker container available not on exposed port?

I have Eureka from Spring Cloud started inside docker container. This is my Dockerfile for building and exposing Eureka:
FROM maven:3.5-jdk-8 AS build
COPY src /home/eureka/src
COPY pom.xml /home/eureka
RUN mvn -f /home/eureka/pom.xml clean package
FROM openjdk:8-jdk-alpine
COPY --from=build /home/eureka/target/service-registry-1.0-SNAPSHOT.jar /usr/app/service-registry-1.0-SNAPSHOT.jar
ENTRYPOINT ["java","-jar","/usr/app/service-registry-1.0-SNAPSHOT.jar"]
EXPOSE 8761
This is my docker compose file:
version: '2.1'
services:
eureka-service-registry-app:
build: eureka-service-registry-app
ports:
- "8761-8761"
There are more app will be in infrastructure, but right now they are commented.
I start docker-compose up, process looks ok, but when I want to check Eureka web dashboard by localhost:8761 this host is unavailable. Hm, ok. In list of my containers I see the follow:
0.0.0.0:32772->8761/tcp
and localhost:32772 is available and Eureka is alive. Moreover if I start docker-compose up again this port will be incremented and new port where Eureka will be available will be 32773. Thus I see there some schema but I don't understand how to make this port stable and regular as Eureka has been started with no Docker on 8761

You define a port range with
ports:
- "8761-8761"
Please change it to
ports:
- "8761:8761"

As others already pointed out: The port exposing in the docker-compose.yml should be changed to
-"8761:8761".
However I see more points to that.
The default port of Eureka is (as far as I know) 1111.
Are you exposing the correct port?
Furthermore be careful when using eureka in combination with docker.
They might register themselves with localhost or their internal IP-Address from the
Docker container, which might not be available from the other docker containers.
Consider having a look at the following application proporties (or environment variables):
eureka.instance.prefer-ip-address=false
eureka.instance.ip-address=$HOST_IP_ADDRESS
eureka.instance.hostname=localhost

How to override embedded DNS server for Docker in /etc/resolv.conf from a docker-compose file

I am using a docker-compose command to create and start my containers.
My Docker Version
docker --version
Docker version 17.09.0-ce, build afdb6d4
My Docker-Compose version
docker-compose --version
docker-compose version 1.16.1, build 6d1ac21
The .yml file that I'm using looks something like this:
(Note that I've just shortened it to take sensitive things out)
---
services:
zookeeper:
image: "zookeeper"
server-1:
cap_add:
- "NET_ADMIN"
server-0:
cap_add:
- "NET_ADMIN"
dns:
- 8.8.8.8
- 9.9.9.9
environment:
SERVER_ID: 0
NETEM_HOSTS: ""
LOSS_VALUES: ""
MAX_RATE_VALUES: ""
DELAY_VALUES: ""
image: "cloud.mycompany.com:5000/server-0:latest"
fakedns:
image: "cloud.mycompany.com:5000/fakedns:latest"
version: "3.3"
Then I start using:
docker-compose --file compose.yml up -d
My Question is this:
1) After containers come up... when I go into a container, for e.g. in this case server-0, I don't see the /etc/resolv.conf file updated to use these nameservers. Instead it uses the embedded dns of docker which is 127.0.0.11
2) How do I make sure that it uses what I specify in file that is used by docker-compose
3) I tried to do this with the command and it seems to work, but I need to do from compose-file
docker run -p 4000:53 --dns=8.8.8.8 cloud.mycompany.com:5000/server-0:latest
4) Ideally, I want it to have the IP address of the container 'fakedns' so that it uses this one instead of the embedded one #127.0.0.11

You won't see custom DNS servers in /etc/resolv.conf but Docker's resolver will forward DNS requests to them.
User Defined Networks and DNS
Docker compose definitions that are v2+ create a user defined network by default.
Docker with a user defined network uses an embedded DNS server so that Docker can respond for local container requests (service discovery).
For any DNS hosts Docker can not resolve, the request will be forwarded onto a DNS server. This is either the system default server, the server configured in dockerd or the DNS server configured for the container at run time.
Docker DNS
Be careful when using internal DNS servers. Things in the Docker daemon will break if you point the systems DNS at a container as you create a chicken or the egg problem, Docker needs DNS to start but can't start the container to provide DNS.
As your example config is only setting the DNS for one app container it should be ok, but make sure the DNS container is up and healthy before your application.

How to run undertow java app with docker

I am using undertow for my applications with docker.
I am able to do the following
create fat jar
create docker image from that
Run that docker image
Listing on 8080 and added EXPOSE 8080 in Docker file
curl my url from INSIDE the CONTAINER , curl localhost:8080/sample
I am facing some weird problem,
And My compose file is
version: '2'
services:
login:
image: my-image
ports:
- "8080:8080"
with 8080 port I am not able to access the url.
My Dockerfile
FROM openjdk:8-jre
COPY ./target/*-with-dependencies.jar /jars/service-jar.jar
EXPOSE 8080
CMD java -cp /jars/service-jar.jar my.Main
My Undertow Listener
Undertow server = Undertow.builder()
.addHttpListener(8080, "localhost")
.setHandler(path)
.build();
I got some link in google still not able to make it work
http://lists.jboss.org/pipermail/undertow-dev/2014-October/000999.html

fixed the issue , by listening the ip to the docker containers ip address .
I changed my listener to
Undertow server = Undertow.builder()
.addHttpListener(8080, InetAddress.getLocalHost().getHostAddress())
.setHandler(path)
.build();
Now it working fine.
"The external IP is something completely different. So in summary you
must set the host server for undertow as the Internal IP in the
Iptables created by docker"
I missed to read this line in my reference link (http://lists.jboss.org/pipermail/undertow-dev/2014-October/000999.html).
My boss find out that .

How are you running your docker image?
Are you publishing port?
docker run -p 8080:8080 ...
Related documentation