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Can't connect to SQL server from Container

My Python container is throwing the error below when trying to connect to my SQL DB hosted on a server:
mariadb.OperationalError: Can't connect to server on 'xxxxxxxxxxx.jcloud-ver-jpc.ik-server.com' (115)
I am trying to run my container from my server as well. If I run the exact same container from my machine, I can connect to the SQL DB.
I am new to Docker, so just for info, here is my Dockerfile:
FROM python:3.10-slim-buster
WORKDIR /app
COPY alpha_gen alpha_gen
COPY poetry.lock .
COPY pyproject.toml .
# install basic utils
RUN apt-get update
RUN apt-get install curl -y
RUN apt-get install gcc -y
# install MariaDB connector
RUN apt install wget -y
RUN wget https://downloads.mariadb.com/MariaDB/mariadb_repo_setup
RUN chmod +x mariadb_repo_setup
RUN ./mariadb_repo_setup \ --mariadb-server-version="mariadb-10.6"
RUN apt install libmariadb3 libmariadb-dev -y
# install poetry
RUN curl -sSL https://install.python-poetry.org | python3 -
ENV PATH="${PATH}:/root/.local/bin"
RUN poetry config virtualenvs.in-project true
# install dependencies
RUN poetry install
CMD poetry run python alpha_gen/main.py --load_pre_process
Any ideas ?

Problem solved. Apparently there is a private port to use for communication from the server and a public port for communication from outside the server. I was using the public one so it was not working.

Unable to run Flask App using Docker in Windows-10

I've installed and configured docker (as per documentation) and I am trying to build a flask application using tiangolo/uwsgi-nginx-flask:python3.8. I've built a hello-world application, and have tested it locally by running python manage.py and the application runs successfully. Link to full Code-File.
My docker version and installation is as below:
Dockerfile:
FROM tiangolo/uwsgi-nginx-flask:python3.8
ENV INSTALL_PATH /usr/src/helloworld
RUN mkdir -p $INSTALL_PATH
# install net-tools
RUN apt-get update \
&& DEBIAN_FRONTEND=noninteractive apt-get install -y \
net-tools \
&& apt-get clean \
&& rm -rf /var/lib/apt/lists/*
# set working directory
WORKDIR $INSTALL_PATH
# setup flask environment
# install all requirements
COPY requirements.txt requirements.txt
RUN pip install -r requirements.txt
# copy all files and folder to docker
COPY . .
# run the application in docker environment
CMD [ "python", "./manage.py" ]
I built the application with docker build --tag hello-world:test . and running the application as: docker run -d -p 5000:5000 hello-world:test successfully.
However, I'm unable to open the application in localhost:5000 or 0.0.0.0:5000 or any other port. The application is running, as I can see it from the CLI:
But, from browser the page is not reachable:
The question mentions to check the IP address:
docker inspect -f "{{ .NetworkSettings.Networks.nat.IPAddress }}" hungry_engelbart
>> <no value>
Found another solution at this link, but docker-machine is currently deprecated.
I'm new to docker, but I have tried to run the same thing following this tutorial, but faced similar issues.

Finally, I am able to solve this. I had to configure a new inbound rules under Windows Firewall > Advanced Settings > Inbound Rules > New Inbound Rules. Create a new rule that will allow a range of local IP addresses, which in my case was 198.168.0.1:198.168.0.100. Finally, you need to run the application at 0.0.0.0 as pointed by #tentative in the comments. :)

Python Docker error: [FreeTDS][SQL Server]Unable to connect to data source (0) (SQLDriverConnect) on SQL Server

I'm trying to make a simple MS SQL Server call from Python by using Docker. The SQL connection is able to establish if I run the python execute script, but it won't work from Docker.
My code is below
Dockerfile
from python:3
WORKDIR /code
COPY requirements.txt .
RUN apt-get update \
&& apt-get install unixodbc -y \
&& apt-get install unixodbc-dev -y \
&& apt-get install freetds-dev -y \
&& apt-get install freetds-bin -y \
&& apt-get install tdsodbc -y \
&& apt-get install --reinstall build-essential -y
RUN echo "[FreeTDS]\n\
Description = FreeTDS Driver\n\
Driver = /usr/lib/x86_64-linux-gnu/odbc/libtdsodbc.so\n\
Setup = /usr/lib/x86_64-linux-gnu/odbc/libtdsodbc.so" >> /etc/odbcinst.ini
#Pip command without proxy setting
RUN pip install -r requirements.txt
COPY src/ .
CMD ["python", "./producer.py"]
producer.py
import pyodbc
connP = pyodbc.connect('driver={FreeTDS};'
'server={MYSERV01\SQLEXPRESS};'
'database=ABCD;'
'uid=****;'
'pwd=*****')
requirement.txt
kafka-python
pyodbc==4.0.28
Error message
I referred to this article and did. I searched online for resolutions and tried several steps, but nothing helped. I'm pretty new to Docker and no experience in Python, so any help would be really good. Thanks in advance!

In your pyodbc.connect try to give the server as '0.0.0.0' instead of any other value.
If you want to debug it from inside the container, then comment the last CMD line of your Dockerfile.
Build your Docker container
docker build -f Dockerfile -t achu-docker-container .
Run your Docker Container
docker run -it achu-docker-container /bin/bash
This will place you inside the container. This is like, ssh to a different machine.
Go to your WORKDIR
cd code
python ./producer.py
What do you get the above above? (If you install any editor using apt-get install vim you will be able to interactively edit the producer.py file and fix your problem from inside the running container.
Then you can move your changes to your source Dockerfile and build a new image and container with it.

I was trying to connect to the local SQL Server database. I referred many articles and figured out that the following code works:
the server should have host.docker.inter,<port_no> -- this was the catch. When it comes to dedicated database where the sql server is different from the docker image, the server name is provided directly, but when both image and database are in same server, the following code works. Please check the port number in the SQL Configuration TCP Address (IP4All)

Correct way for deploying dbt with docker and cloud run

I'm trying to deploy dbt on a Google cloud run service with a docker container. following david vasquez and dbt Docker images However when trying to deploy the builded image to cloud run. I'm getting an error.
ERROR: (gcloud.run.deploy) Cloud Run error: Container failed to start. Failed to start and then listen on the port defined by the PORT environment variable. Logs for this revision might contain more information.
This is my dockerfile
FROM python:3.8.1-slim-buster
RUN apt-get update && apt-get dist-upgrade -y && apt-get install -y --no-install-recommends git software-properties-common make build-essential ca-certificates libpq-dev && apt-get clean && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*
COPY requirements/requirements.0.17.0rc4.txt ./requirements.0.17.0rc4.txt
RUN pip install --upgrade pip setuptools
RUN pip install -U pip
RUN pip install dbt==0.17.0
RUN pip install --requirement ./requirements.0.17.0rc4.txt
RUN useradd -mU dbt_user
ENV PYTHONIOENCODING=utf-8
ENV LANG C.UTF-8
ENV PORT = 8080
ENV HOST = 0.0.0.0
WORKDIR /usr/app
VOLUME /usr/app
USER dbt_user
CMD ['dbt', 'run']
I understand the health check fails because it can't find a port to listen to, except i specify one in my ENV
Can anyone help me with a solution? thx in advance

According to the documentation one of the requirements to deploy an application on Cloud Run is to listen requests on 0.0.0.0 and expose a port:
The container must listen for requests on 0.0.0.0 on the port to which requests are sent. By default, requests are sent to 8080, but you can configure Cloud Run to send requests to the port of your choice.
dbt is a command line tool which means it doesn't expose any PORT, hence when you're trying to deploy Cloud Run and it verifies if the build is listening it fails with the mentioned error.

Run python process in docker in linux screen in detach mode

I have written Dockerfile for my python application.
Requirement is :
Install & start mysql server.
Run the application in screen in detach mode.
Below is my Dockerfile:
FROM ubuntu:16.04
# Update OS
RUN apt-get update
RUN apt-get -y upgrade
# Install Python
RUN apt-get install -y python-dev python-pip screen npm vim net-tools
RUN DEBIAN_FRONTEND=noninteractive apt-get -y install mysql-server python-mysqldb
RUN mkdir -p /usr/src/app
WORKDIR /usr/src/app
COPY requirements.txt /usr/src/app
RUN pip install --no-cache-dir -r requirements.txt
COPY src /usr/src/app/src
COPY ./src/nsd.ini /etc/
RUN pwd
RUN cd /usr/src/app
RUN service mysql start
RUN /bin/bash -c "chmod +x src/run_demo_app.sh && src/run_demo_app.sh"
Below is the content of bash script
$ cat src/run_demo_app.sh
$ screen -dm bash -c "sleep 10; python -m src.app";
The problem is Mysql doesn't start. I need to start it manually from container.
Also, the screen becomes dead and application do not start. Manually running the script works fine.

So this is a understanding gap and nothing else. Note below issues in your docker file
Never use service command
RUN service mysql start
Docker doesn't use a init system. So never use a service command inside docker.
Don't put everything in same container
You should not put everything in the same container. So mysql should run in its own container and python in its own
Use official images
You don't need to re-invent the wheel. Use official images as much as possible. You should be using mysql and python images in your case
Use docker-compose when multiple services are needed
In your case since you are requiring multiple services, use docker-compose.
No need to use screen in docker
Screen is used when your want your process to be running even if your SSH disconnects. So that in not needed in docker. If you run your docker run or docker-compose up command with an additional -d flag then your container will automatically be launched in background