If you have a docker image and don’t have the Dockerfile used to create the image, dfimage can help you re-create Dockerfile. To find information about an image, you can use the command “docker history IMAGE_ID”. History command will show all actions taken on the image, including the commands used. You can use this information […]
To create a docker container with Apache, create a Dockerfile
|
1 2 3 |
mkdir my-app cd my-app vi Dockerfile |
Paste following content into the Dockerfile
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 |
from ubuntu:20.04 ARG DEBIAN_FRONTEND=noninteractive RUN apt-get update && apt-get install -y apache2 RUN echo 'Hello World!' > /var/www/html/index.html RUN echo '. /etc/apache2/envvars' > /root/run_apache.sh && \ echo 'mkdir -p /var/run/apache2' >> /root/run_apache.sh && \ echo 'mkdir -p /var/lock/apache2' >> /root/run_apache.sh && \ echo '/usr/sbin/apache2 -D FOREGROUND' >> /root/run_apache.sh && \ chmod 755 /root/run_apache.sh EXPOSE 80 CMD /root/run_apache.sh |
Now build an image with command
|
1 |
docker build -t sevrerok/okapache:1.0 . |
Once image is build, you can see it using docker images command
|
1 2 3 4 5 6 7 |
[root@instance-20210426-0136 my-app]# docker images REPOSITORY TAG IMAGE ID CREATED SIZE sevrerok/okapache 1.2 c3832b03b548 8 minutes ago 214MB sevrerok/okapache 1.1 d1a86f0eb69a 37 minutes ago 214MB ubuntu 20.04 7e0aa2d69a15 2 days ago 72.7MB sevrerok/okapache 1.0 7e0aa2d69a15 2 days ago 72.7MB [root@instance-20210426-0136 my-app]# |
To start a container with the image, run
|
1 |
docker container run -d -p 80:80 sevrerok/okapache:1.0 |
See docker build […]
Odoo is an open source ERP and CRM software written in python. To install Odoo using docker, first install docker using
|
1 |
wget -qO- https://get.docker.com/ | sh |
Odoo use PostgreSQL server to store database. Lets create a postgres docker container.
|
1 |
docker run -d -e POSTGRES_USER=odoo -e POSTGRES_PASSWORD=your-password-here -e POSTGRES_DB=postgres --name odoo-db postgres:10 |
In above command, replace your-password-here with a secure password. Create a Odoo container with
|
1 |
docker run -d -p 127.0.0.1:8069:8069 -p 127.0.0.1:8072:8072 --name odoo --link odoo-db:db -t odoo |
If container did not […]
When you run a docker image, it create a container and run it. After docker container stop, container stays, so you can use it again if required. Some times, you need to delete docker container after it is run. This is useful if your docker container is just a command line executable. In my case, […]
To run PostgreSQL on docker, create a directory for saving the data presistant
|
1 |
mkdir -p /opt/my-postgresql |
run docker container
|
1 2 3 4 5 6 7 |
docker run --name my-postgresql \ -p 5432:5432 \ -e POSTGRES_PASSWORD=serverok123 \ -e POSTGRES_USER=serverok \ -e POSTGRES_DB=serverok \ -v /opt/my-postgresql:/var/lib/postgresql/data \ -d postgres |
In above, change the value for POSTGRES_DB, POSTGRES_USER and POSTGRES_PASSWORD as needed. Connect to PostgreSQL server To connect to PostgreSQL server, run
|
1 |
docker container exec -ti my-postgresql bash |
Now you are inside PostgreSQL conainer, to login, run
|
1 |
psql -U serverok -W |
It will ask for […]
I have a docker container, that i need to start on server boot. The docker-compose.yml file i used to create this docker container is
|
1 2 3 4 5 6 7 8 9 10 11 |
[root@cp03 serverok-rubycms]# cat docker-compose.yml version: '3' services: web: image: serverok/rubycms:1.0 command: bash -c "rm -f tmp/pids/server.pid && cd /myapp && source /etc/profile.d/rvm.sh && script/server -e production" volumes: - /home/naiwnyc/cms:/myapp ports: - "3000:3000" [root@cp03 serverok-rubycms]# |
With above docker-compose.yml file. i have to start docker container manually after server reboot. To make it auto start, add the line
|
1 |
restart: always |
Here is the modified docker-compose.yml file.
|
1 2 3 4 5 6 7 8 9 10 11 12 |
[root@cp03 serverok-rubycms]# cat docker-compose.yml version: '3' services: web: image: serverok/rubycms:1.0 restart: always command: bash -c "rm -f tmp/pids/server.pid && cd /myapp && source /etc/profile.d/rvm.sh && script/server -e production" volumes: - /home/naiwnyc/cms:/myapp ports: - "3000:3000" [root@cp03 serverok-rubycms]# |
[…]
When running docker-compose on CentOS 7, i get following error
|
1 2 3 |
[root@cp03 serverok-rubycms]# docker-compose up docker-compose: error while loading shared libraries: libz.so.1: failed to map segment from shared object: Operation not permitted [root@cp03 serverok-rubycms]# |
To fix the error, do the following
|
1 |
mv /usr/local/bin/docker-compose /usr/local/bin/docker-compose-bin |
Now create a new file
|
1 |
vi /usr/local/bin/docker-compose |
Add following content
|
1 2 3 4 |
Make it executable
|
1 |
chmod 755 /usr/local/bin/docker-compose |
Create temp folder
|
1 |
mkdir -p /opt/compose-tmp |
Now docker-compose will work. […]
Create Python Flask Docker Container […]
Create a folder and change to the folder
|
1 2 |
mkdir python-flask cd python-flask |
Create file
|
1 |
vi Dockerfile |
Add following content
|
1 2 3 4 5 6 7 8 9 10 |
FROM python:2.7-slim WORKDIR /app COPY . /app RUN pip install -r requirments.txt EXPOSE 8080 CMD ["python", "app.py"] |
Create file requirements.txt, add “Flask” to it.
|
1 |
echo "Flask" > requirments.txt |
Now lets create our Python Flask Application
|
1 |
vi app.py |
Add following content
|
1 2 3 4 5 6 7 8 9 10 11 12 |
from flask import Flask import os import socket app = Flask(__name__) @app.route("/") def hello(): return "<h1>Ok, World</h1>" if __name__ == "__main__": app.run(host="0.0.0.0", port=8080) |
To test Flask application locally, install Flask using pip
|
1 |
sudo pip install Flask |
Now run the application using
|
1 |
python app.py |
Now you will […]
Login to gcloud with
|
1 |
gcloud auth login |
Set default region
|
1 |
gcloud config set compute/zone us-central1-a |
To create a cluser, run
|
1 |
gcloud container clusters create CLUSTER-NAME |
To create a cluster with 2 nodes, run
|
1 |
gcloud container clusters create CLUSTER-NAME --num-nodes 2 |
To specify compute engine type during cluster creation, run
|
1 |
gcloud container clusters create CLUSTER-NAME --num-nodes 2 --machine-type n1-standard-2 |
You can also specify scopes, this allow you to give the cluster permission to access other google cloud resources. For example […]