I created a Postgres container with docker
sudo docker run -d \
--name dev-postgres \
-e POSTGRES_PASSWORD=test \
-e POSTGRES_USER=test \
-v ${HOME}/someplace/:/var/lib/postgresql/data \
-p 666:5432 \
postgres
I give the Postgres instance test as a username and password as specified in the doc.
The Postgres port (5432) inside the container is linked to my 666 port on the host.
Now I want to try this out using psql
psql --host=localhost --port=666 --username=test
I'm prompted to enter the password for user test and after entering test, I get
psql: error: FATAL: password authentication failed for user "test"
There are different problems that can cause this
The version of Postgres on the host and the container might not be the same
If you have to change the docker version of Postgres used, make sure that the container with the new version is not crashing. Trying to change the version of Postgres while using the same directory for data might cause problem as the directory was initialized with the wrong version.
You can use docker logs [container name] to debug if it crashes
There might be a problem with the volumes used by docker (something with cached value preventing the creation of a new user when env variable change) if you changed the env parameters.
docker stop $(docker ps -qa) && docker system prune -af --volumes
If you have problem with some libraries that use Postgres, you might need to install some package to allow libraries to work with Postgres. Those two are the one Stack Overflow answers often reference.
sudo apt install libpq-dev postgresql-client
Other problems seem to relate to problems with docker configuration.
Related
I have been trying since yesterday to connect to a ChainLink node and I was not able to.
I followed the steps at this website
I am having a problem with "Set the Remote DATABASE_URL Config" (I think that this is my only error because of the [ERROR] listed below, I do not know if I am doing something else wrong since every command was executed without error)
I am using the Docker option to create the database listed here.
I am always having this error:
"[ERROR] unable to lock ORM: failed to connect to host=localhost user=some-postgres database=postgres: dial error (dial tcp [::1]:5432: connect: cannot assign requested address) logger/default.go:155 stacktrace=github.com/smartcontractkit/chainlink/core/logger.Errorf
/chainlink/core/logger/default.go:155"
After writing in my Ubuntu Terminal (ON WINDOWS 10):
"cd ~/.chainlink-kovan && docker run -p 6688:6688 -v ~/.chainlink-kovan:/chainlink -it --env-file=.env smartcontract/chainlink:0.10.1 local n"
I do not know how to connect to the database and what to write as attributes. All of the other steps and installs I have accomplished successfully.
I just want to know how to create a database on PostgreSQL and connect it to Docker as explained on the ChainLink website and write the appropriate command in the Ubunto terminal (for the "Remote DATABASE_URL Config PostgreSQL" step) so that I can run my node.
Thanks! (PS: I am a beginner and your help is much appreciated, and if I forgot to mention any important information please let me know so that I add it)
A comprehensive 101 for docker-postgres can be found here: https://hackernoon.com/dont-install-postgres-docker-pull-postgres-bee20e200198
Basically, you need to deploy a postgres db with docker
Pre-Reqs:
Create a dir for you docker/postgres:
mkdir -p $HOME/docker/volumes/postgres
Example:
docker run --rm --name pg-docker -e POSTGRES_USER=<any_desired_name> -e POSTGRES_PASSWORD=docker -e POSTGRES_DB=<any_db_name> -d -p 5432:5432 -v $HOME/docker/volumes/postgres:/var/lib/postgresql/data postgres
For postgres username, it can be anything like "super_chain" or etc.
For postgres db, it can be "chainlink"
After, docker is up and running. Just follow up the docs tut, where you need to write the DB URL to the .env file
Cheers
I have installed Postgres 12 on Ubuntu by building it from source and I am facing two issues:
Although I followed the installation manual from Postgrez, every time I restart my computer, my Postgres server stopz and is no longer seen as a running process.
To start it the first time after install, I do this from the terminal:
/usr/local/pgsql/bin/initdb -D /usr/local/pgsql/data
/usr/local/pgsql/bin/pg_ctl -D /usr/local/pgsql/data -l logfile start
After a restart, to start DB again when I run: /usr/local/pgsql/bin/initdb -D /usr/local/pgsql/data, it throws this error:
initdb: error: directory "/usr/local/pgsql/data" exists but is not empty
If you want to create a new database system, either remove or empty
the directory "/usr/local/pgsql/data" or run initdb
with an argument other than "/usr/local/pgsql/data".
Does that mean that every time I start Postgres after a restart, I have to create a new /data directory?
Upon installing Postgres sing pip or pip3, one can just switch user to postgres and run psql to enter postgres, however now I have to run "/usr/local/bin/psql". Please note I have exported all the paths per https://www.postgresql.org/docs/12/installation.html. How can I fix this? Can an alias be set for this?
After a restart, to start DB again when I run:
/usr/local/pgsql/bin/initdb -D /usr/local/pgsql/data, it throws this
error:
Does that mean that every
time I start Postgres after a restart, I have to create a new /data
directory?
No, quite the opposite. You don't need to initdb after the first time, you just need to start. It is your attempt to initdb when you don't need to which is causing the error message. Note that attempting to initdb isn't doing any harm, because it refused to run. It just generates log/console noise.
Upon installing Postgres sing pip or pip3, one can just switch user to
postgres and run psql to enter postgres, however now I have to run
"/usr/local/bin/psql". Please note I have exported all the paths per
https://www.postgresql.org/docs/12/installation.html. How can I fix
this?
I don't know what your first sentence means, as you don't use pip or pip3 to install PostgreSQL (or at least, the docs don't describe doing so) although you might use them to install psycopg2 to enable python to talk to PostgreSQL.
You could use an alias, but it would probably make more sense to edit ~/.bash_profile to set the PATH, as described from the page you linked to under Environment Variables.
You have to register postgreSQL as a service.
run this:
pg_ctl register [-N servicename] [-U username] [-P password] [-D datadir] [-S a[uto] | d[emand] ] [-w] [-t seconds] [-s] [-o options]
Example:
pg_ctl register -N postgresql -U OS_username -P OS_password -D '/etc/postgresql/12/data' -w
More info in the manual: pg_ctl
Notes:
Username and Password is related to the OS, not postgresql
If you have doubts read the manual.
/usr/local/pgsql/bin/pg_ctl start -D '/usr/local/pgsql/data'
Export following in postgres user account's ~/.bashrc:
LD_LIBRARY_PATH=/usr/local/pgsql/lib
export LD_LIBRARY_PATH
PATH=/usr/local/pgsql/bin:$PATH
export PATH
I want do use a docker container to simulate my production environment, so I installed the db and the server in the same container, and not each in his own.
This is my dockerfile:
FROM debian
RUN apt update
RUN apt install postgresql-9.6 tomcat8 tomcat8-admin -y
RUN service postgresql start
RUN service postgresql status # says postgres is down
RUN su - postgres ;
RUN createdb db_example # fails !!!
RUN psql -c "CREATE USER springuser WITH PASSWORD 'test123';"
RUN exit
RUN service tomcat8 start
COPY target/App-1.0.war /var/lib/tomcat8/webapps/
CMD ["/bin/bash"]
The problem is that the database is down so I am uable to create the user and the database.
If I start the a debian docker container and do this steps per hand everything works fine.
Thanks for your help
All the recommendations in the comments are correct, it's better to keep services in different containers.
Nevertheless and just to let you know, the problem in the Dockerfile is that starting services in RUN statements is useless. For every line in the Dockerfile, docker creates a new image. For example RUN service postgresql start, it may start postgresql during docker build, but it doesn't persist in the final image. Only the filesystem persist from one step to another, not the processes.
Every process need to be started in the entrypoint, this is the only command that's called when you exec docker run:
FROM debian
RUN apt update
RUN apt install postgresql-9.6 tomcat8 tomcat8-admin -y
COPY target/App-1.0.war /var/lib/tomcat8/webapps/
ENTRYPOINT["/bin/bash", "-c", "service postgresql start && service postgresql status && createdb db_example && psql -c \"CREATE USER springuser WITH PASSWORD 'test123';\" && service tomcat8 start && sleep infinity"]
(It may have problems with quotes on psql command)
I have the problem hat in the war file the localhost for the database war hard coded.
Thanks to Light.G, he suggested me to use --net=host for the container, so now there is one container with the database and one with the tomcat server.
This are the steps I followed.
Build the docker image
docker build -t $USER/App .
Start a postgres database
We are using the host namespace it is not possible to run another programm on the post 5432.
Start the postgres container like this:
docker run -it --rm --net=host -e POSTGRES_USER='springuser' -e POSTGRES_DB='db_example' -e POSTGRES_PASSWORD='test123' postgres
Start the tomcat
Start the App container, with this command:
docker run -it --net=host --rm $USER/App
I need to create plpythonu extension on the postgres:10.3 image. For this, I extended the image with an installation command:
FROM postgres:10.3
RUN apt update && apt install -y postgresql-plpython-10
Now I need to run a psql command create extension plpythonu;. But at this point the postgres server is not running yet, so when running docker build . I get an error:
Step 3/3 : RUN psql -c "create extension plpythonu;";
---> Running in 037066c120ea
psql: could not connect to server: No such file or directory
Is the server running locally and accepting
connections on Unix domain socket "/var/run/postgresql/.s.PGSQL.5432"?
How do I fit this command in? And is there a way to do this without copypasting the entire docker-entrypoint.sh from the original postgres image? Maybe there's a way to specify this in docker-compose?
When step-2 is over you Postgres database down, that is why in Step-3 database is not running.
You can combine step-2 and step-3 together.
RUN apt update && \
apt install -y postgresql-plpython-10 && \
psql -c "create extension plpythonu;"
It means && (logical and) if previous commands successfully over then only execute next one.
I'm running postgres inside a docker container to limit the amount of system resources it has access to. I'm having some trouble understanding how to make the data persistent. I've read the following articles:
https://www.andreagrandi.it/2015/02/21/how-to-create-a-docker-image-for-postgresql-and-persist-data/
http://container42.com/2013/12/16/persistent-volumes-with-docker-container-as-volume-pattern/
Which suggest using a data only container, and then having my postgres container link to it. What I'm failing to understand is; what's the advantage to this? As far as I can tell, if for some reason the docker-machine shut down (for example; moving it to a different physical machine), the data only container stops running, and all of it's contents are lost? I've tried creating a volume in the postgres container, but it doesn't actually seem to save anything to the disk.
Here's my docker file. What am I doing wrong?
FROM ubuntu
MAINTAINER Andrew Broadbent <andrew.broadbent#manchester.ac.uk>
# Add the PostgreSQL PGP key to verify their Debian packages.
# It should be the same key as https://www.postgresql.org/media/keys/ACCC4CF8.asc
RUN apt-key adv --keyserver hkp://p80.pool.sks-keyservers.net:80 --recv-keys B97B0AFCAA1A47F044F244A07FCC7D46ACCC4CF8
# Add PostgreSQL's repository. It contains the most recent stable release
# of PostgreSQL, ``9.3``.
RUN echo "deb http://apt.postgresql.org/pub/repos/apt/ precise-pgdg main" > /etc/apt/sources.list.d/pgdg.list
# Install ``python-software-properties``, ``software-properties-common`` and PostgreSQL 9.3
# There are some warnings (in red) that show up during the build. You can hide
# them by prefixing each apt-get statement with DEBIAN_FRONTEND=noninteractive
RUN apt-get update && apt-get install -y python-software-properties software-properties-common postgresql-9.3 postgresql-client-9.3 postgresql-contrib-9.3
# Note: The official Debian and Ubuntu images automatically ``apt-get clean``
# after each ``apt-get``
# Run the rest of the commands as the ``postgres`` user created by the ``postgres-9.3`` package when it was ``apt-get installed``
USER postgres
# Create a PostgreSQL role named ``docker`` with ``docker`` as the password and
# then create a database `docker` owned by the ``docker`` role.
# Note: here we use ``&&\`` to run commands one after the other - the ``\``
# allows the RUN command to span multiple lines.
RUN /etc/init.d/postgresql start &&\
psql --command "CREATE USER docker WITH SUPERUSER PASSWORD 'docker';" &&\
createdb -O docker docker
# Complete configuration
USER root
RUN echo "host all all 0.0.0.0/0 md5" >> /etc/postgresql/9.3/main/pg_hba.conf
RUN echo "listen_addresses='*'" >> /etc/postgresql/9.3/main/postgresql.conf
# Expose the PostgreSQL port
EXPOSE 5432
# Add VOLUMEs to allow backup of config, logs and databases
RUN mkdir -p /var/run/postgresql && chown -R postgres /var/run/postgresql
VOLUME ["/etc/postgresql", "/var/log/postgresql", "/var/lib/postgresql"]
# Set the default command to run when starting the container
USER postgres
CMD ["/usr/lib/postgresql/9.3/bin/postgres", "-D", "/var/lib/postgresql/9.3/main", "-c", "config_file=/etc/postgresql/9.3/main/postgresql.conf"]
This one answers your question about data container:
docker mounting volumes on host
Regarding to your dockerfile, I would suggest you either:
1) use data container pattern
2) mount the volume to host machine by specifying: docker run -v [host-path]:[container-path] ..., so that data will be kept at one place in your host and will not be lost after the container is removed.
Ref: https://docs.docker.com/engine/tutorials/dockervolumes/#/mount-a-host-directory-as-a-data-volume