Previously, to access a file in a running dokku instance I would run:
docker ps to get the container ID followed by
ls /var/lib/docker/aufs/diff/<container-id>/app/...
note: I'm just using 'ls' as an example command. I ultimately want to reference a particular file.
This must have changed, as the container ID is no longer accessible via this path. There are loads of dirs in that folder, but none that match any of the running containers.
It seems like mounting a volume for the entire container would be overkill in this scenario. I know I can access the file system using dokku run project-name ls, and also docker exec <container-id> ls, but neither of those will satisfy my use case.
To explain a bit more fully, in my dokku project, I have some .sql files that I'm using to bootstrap my postgres DB. These files get pushed up via git push with the rest of the project.
I'm hoping to use the postgres dokku plugin to run the following:
dokku postgres:connect db-name < file-name.sql
This is what I had previously been doing using:
dokku postgres:connect db-name < /var/lib/docker/aufs/diff/<container-id>/app/file-name.sql but that no longer works.
Any thoughts on this? Am I going about this all wrong?
Thanks very much for any thoughts.
Here's an example:
dokku apps:list
=====> My Apps
DummyApp
dokku enter DummyApp
Enter bash to the DummyApp container.
Never rely on the /var/lib/docker file system paths as most of the data stored there is dependent on the storage driver currently in use so it is subject to change.
cat the file from an existing container
docker exec <container> cat file.sql | dokku postgres:connect db-name
cat the file from an image
docker run --rm <image> cat file.sql | dokku postgres:connect db-name
Copy file from an existing container
docker cp <container>:file.sql file.sql
dokku postgres:connect db-name < file.sql
Related
I'm a newbie to Docker, I'm working on a project that written by another developer, the project is running on Digital Ocean Ubuntu 18.04. It consists of 2 containers (1 container for Django App, 1 container for PostgreSQL database).
It is required from me now to get a backup of database, I found a bash file written by previous programmer:
### Create a database backup.
###
### Usage:
### $ docker-compose -f <environment>.yml (exec |run --rm) postgres backup
set -o errexit
set -o pipefail
set -o nounset
working_dir="$(dirname ${0})"
source "${working_dir}/_sourced/constants.sh"
source "${working_dir}/_sourced/messages.sh"
message_welcome "Backing up the '${POSTGRES_DB}' database..."
if [[ "${POSTGRES_USER}" == "postgres" ]]; then
message_error "Backing up as 'postgres' user is not supported. Assign 'POSTGRES_USER' env with another one and try again."
exit 1
fi
export PGHOST="${POSTGRES_HOST}"
export PGPORT="${POSTGRES_PORT}"
export PGUSER="${POSTGRES_USER}"
export PGPASSWORD="${POSTGRES_PASSWORD}"
export PGDATABASE="${POSTGRES_DB}"
backup_filename="${BACKUP_FILE_PREFIX}_$(date +'%Y_%m_%dT%H_%M_%S').sql.gz"
pg_dump | gzip > "${BACKUP_DIR_PATH}/${backup_filename}"
message_success "'${POSTGRES_DB}' database backup '${backup_filename}' has been created and placed in '${BACKUP_DIR_PATH}'."
my first question is:
is that command right? i mean if i ran:
docker-compose -f production.yml (exec |run --rm) postgres backup
Would that create a backup for my database at the written location?
Second question: can I run this command while the database container is running? or should I run docker-compose down then run the command for backup then run docker-compose up again.
Sure you can run that script to backup, one way to do it is executing a shell in container with docker-compose exec db /bin/bash and then run that script.
Other way is running a new postgres container attached to the postgres container network:
docker run -it --name pgback -v /path/backup/host:/var/lib/postgresql/data --network composeNetwork postgres /bin/bash
this will create a new postgres container attached to the network created with compose, with a binding volume attached, then you can create this script in the container and back up the database to the volume to save it to other place out of container.
Then when you want to backup simple start docker container and backup:
docker start -a -i pgback
You dont need to create other compose file, just copy the script to he container and run it, also you could create a new postgres image with the script and run it from CMD, just to run the container, there are plenty ways to do it.
I am using a postgis/postgis Docker image to set a database server for my application.
The database server must have a tablespace created, then a database.
Then each time another application will start from another container, it will run a Liquibase script that will update the database schema (create tables, index...) when needed.
On a terminal, to prepare the database container, I'm running these commands :
# Run a naked Postgis container
sudo docker run --name ecoemploi-postgis
-e POSTGRES_PASSWORD=postgres
-d -v /data/comptes-france:/data/comptes-france postgis/postgis
# Send 'bash level' commands to create the directory for the tablespace
sudo docker exec -it ecoemploi-postgis
bin/sh -c 'mkdir /tablespace && chown postgres:postgres /tablespace'
Then to complete my step 1, I have to run SQL statements to create the tablespace in a PostGIS point of view, and create the database by a CREATE DATABASE.
I connect myself, manually, under the psql of my container :
sudo docker exec -it ecoemploi-postgis bin/sh
-c 'exec psql -h "$POSTGRES_PORT_5432_TCP_ADDR"
-p "$POSTGRES_PORT_5432_TCP_PORT" -U postgres'
And I run manally these commands :
CREATE TABLESPACE data LOCATION '/tablespace';
CREATE DATABASE comptesfrance TABLESPACE data;
exit
But I would like to have a container created from a single Dockerfile having done all the needed work. The difficulty is that it has to be done in two parts :
One before the container is started. (creating directories, granting them user:group).
One after it is started for the first time : declaring the tablespace and creating the base. If I understand well the base image I took, it should be done after an entrypoint docker-entrypoint.sh has been run ?
What is the good way to write a Dockerfile creating a container having done all these steps ?
The PostGIS image "is based on the official postgres image", so it should be able to use the /docker-entrypoint-initdb.d mechanism. Any files you put in that directory will be run the first time the database container is started. The postgis Dockerfile already uses this directory to install the PostGIS extensions into the default database.
That means you can put your build-time setup directly into the Dockerfile, and copy the startup-time script into that directory.
FROM postgis/postgis:12-3.0
RUN mkdir /tablespace && chown postgres:postgres /tablespace
COPY createdb.sql /docker-entrypoint-initdb.d/20-createdb.sql
# Use default ENTRYPOINT/CMD from base image
For the particular setup you describe, this may not be necessary. Each database runs in an isolated filesystem space and starts with an empty data directory, so there's not a specific need to create an alternate data directory; Docker style is to just run multiple databases if you need isolated storage. Similarly, the base postgres image will create a database for you at first start (named by the POSTGRES_DB environment variable).
In order to run a container, your Dockerfile must be functional and completed.
you must enter the queries in a bash file and in the last line you have to enter an ENTRYPOINT with this bash script
I wish to store my persists data in my local D:\dockerData\postgres9.6. Below is my docker command
docker pull postgres
docker run -d -v /d/dockerData/postgres9.6:/var/lib/postgresql/data -p 5432:5432 postgres
It successful create a container and I can use pgAdmin to access and create database.
But I found out that there is no file in my D:\dockerData\postgres9.6. I exec bash into the container, there is at least 20+ files inside /var/lib/postgresql/data.
Anyone can point out which part goes wrong?
It depends what kind of Docker you are using on Windows:
Docker Toolbox with VirtualBox: only C:\Users\mylogin is shared by default. D:\ is not mounted.
Docker for Windows with HyperV: only C:\ is mounted by default. Make sure D:\ is a shared drive: see image
I'm on windows 10 with docker version 1.9.1 using docker toolbox
I wanted to put up a quick postgres container, something I've done before with a dockerfile I had laying around.
FROM postgres
ADD create-db.sql /tmp/
ADD drop_create_table.sql /tmp/
ADD db.sql /tmp/
ADD create-db.sh /docker-entrypoint-initdb.d/
It's pretty simple.
and when i run the resulting image. it starts fine.
However at the end it says:
...
server started ALTER ROLE
/docker-entrypoint-sh: running
/docker-entrypoint-initdb.d/create-db.sh :No such file or directory
If I try to do docker run -it <imagename> //bin/bash I can see that the file is indeed there:
root#xxxx:/docker-entrypoint-initdb.d# ls
create-db.sh
but whenever I run it it tells me it's not.
The container promptly stops when it doesn't find the file, so I can't try to ssh into the running container.
I have a problem with my docker container. I need to import data, something like .csv file from my computer to docker container, but I don't know how. I found a command like "docker insert" but it doesn't work.
You can do this using Docker volumes.
docker run -i -t -v /home/user/stuff:/data ubuntu /bin/bash
Where in this example /home/user/stuff is a directory OUTSIDE the container and /data is the directory where that content will be located INSIDE the container.