- Docker Compose Not Seeing Environment Variables On The Hostname
- Docker Compose Not Seeing Environment Variable On The Host Ip
Contribute on GitHub What is Docker Compose? If your Docker application includes more than one container (for example, a webserver and database running in separate containers), building, running, and connecting the containers from separate Dockerfiles is cumbersome and time-consuming. Docker Compose solves this problem by allowing you to use a YAML file to.
Oct 13, 2015 - docker-compose only sets the environment variables specified in the. '/bin/bash' redis -c env you will be able to see your env variables. Docker-compose extend not finding environment variables. Ask Question. Docker compose, running containers in net:host. Passing in environment variables into docker file that is build via a compose yaml. Docker-compose is not setting container_name from environment variable.
You can configure as many containers as you want, how they should be built and connected, and where data should be stored. When the YAML file is complete, you can run a single command to build, run, and configure all of the containers. This guide will explain how the docker-compose.yml file is organized, and show how to use it to create several basic app configurations. Generally the containers in an application built using Docker Compose will all run on the same host. Managing containers running on different hosts usually requires an additional tool, such as. Before You Begin Install Docker CE You will need a Linode with Docker CE installed to follow along with the steps in this guide. These steps install Docker Community Edition (CE) using the official Ubuntu repositories.
Docker Compose Not Seeing Environment Variables On The Hostname
To install on another distribution, see the official. The example docker-compose.yml above uses the environment directive to store MySQL user passwords directly in the YAML file to be imported into the container as environment variables. This is not recommended for sensitive information in production environments.
Instead, sensitive information can be stored in a separate.env file (which is not checked into version control or made public) and accessed from within docker-compose.yml by using the envfile directive. Build an Application from Scratch Create a docker-compose.yml file one section at a time to illustrate the steps of building a multi-container application. Define a Simple Service:.
Create a new docker-compose.yml in a text editor and add the following content: docker-compose.yml. 1 2 3 4 5 6 7 8 version: '3' services: distro: image: alpine restart: always containername: AlpineDistro entrypoint: tail -f /dev/ null Each entry in the services section will create a separate container when docker-compose is run. At this point, the section contains a single container based on the official Alpine distribution:. The restart directive is used to indicate that the container should always restart (after a crash or system reboot, for example). The containername directive is used to override the randomly generated container name and replace it with a name that is easier to remember and work with.
Docker containers exit by default if no process is running on them. Tail -f is an ongoing process, so it will run indefinitely and prevent the container from stopping. The default entrypoint is overridden to keep the container running. Bring up your container: docker-compose up -d. Check the status of your container: docker ps The output should resemble the following: CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 967013c36a27 alpine 'tail -f /dev/null' 3 seconds ago Up 2 seconds AlpineDistro. Bring down the container: docker-compose down Add Additional Services From here you can begin to build an ecosystem of containers. You can define how they work together and communicate.
Reopen docker-compos.yml and add the database service below: docker-compose.yml. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 version: '3' services: distro: image: alpine containername: AlpineDistro restart: always entrypoint: tail -f /dev/ null database: image: postgres:latest containername: postgresdb volumes: -./dumps:/tmp/ ports: - '5432:5432' There are now two services defined:. Distro. Database The Distro service is the same as before.
The Database server contains the instructions for a postgres container, and the directives: volumes: -./dumps:/tmp and ports:-'5432:5432', the first directive maps the containerd /dumps folder to our local /tmp folder. The second directive maps the containers ports to the local host’s ports. Check the running containers: docker ps This command shows the status of the containers, the port mapping, the names, and the last command running on them.
It’s important to note that the postgres container reads “docker-entrypoint” under commands. The Postgres script is the last thing that launches when the container starts. CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES ecc37246f6ef postgres:latest 'docker-entrypoint.' About a minute ago Up About a minute 0.0.0.0:5432-5432/tcp postgresdb 35dab3e712d6 alpine 'tail -f /dev/null' About a minute ago Up About a minute AlpineDistro. Bring down both containers: docker-compose down Add an nginx Service.
Add an nginx container so that your application will be able to serve websites: docker-compose.yml. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 version: '3' services: distro: image: alpine containername: AlpineDistro restart: always entrypoint: tail -f /dev/ null database: image: postgres:latest containername: postgresdb volumes: -./dumps:/tmp/ ports: - '5432:5432' web: image: nginx:latest containername: nginx volumes: -./mysite.template:/etc/nginx/conf.d/mysite.template ports: - '8080:80' environment: - NGINXHOST=example.com - NGINXport= 80 links: - database:db - distro This docker-compose file contains some new directives: environment and links. The first directive sets runtime level options within the container.
Links creates a dependency network between the containers. The nginx container depends on the other two to execute.
In addition, the corresponding containers will be reachable at a hostname indicated by the alias. In this case, pinging db from the web container will reach the database service. While you do not need the links directive for the containers to talk with each other, links can serve as a failsafe when starting the docker-compose application. Start Docker Compose and check the container status: docker-compose up -d docker ps The output should be similar to: CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 55d573674e49 nginx:latest 'nginx -g 'daemon.' 3 minutes ago Up 3 minutes 0.0.0.0:8080-80/tcp nginx ad9e48b2b82a alpine 'tail -f /dev/null' 3 minutes ago Up 3 minutes AlpineDistro 736cf2f2239e postgres:latest 'docker-entrypoint.'
3 minutes ago Up 3 minutes 0.0.0.0:5432-5432/tcp postgresdb. Test nginx by navigating to your Linode’s public IP address, port 8080 in a browser (for example 192.0.2.0:8080). You should see the default nginx landing page displayed. Persistent Data Storage Storing PostgreSQL data directly inside a container is not recommended. Docker containers are intended to be treated as ephemeral: your application’s containers are built from scratch when running docker-compose up and destroyed when running docker-compose down.
In addition, any unexpected crash or restart on your system will cause any data stored in a container to be lost. For these reasons it is important to set up a persistent volume on the host that the database containers will use to store their data. Add a volumes section to docker-compose.yml and edit the database service to refer to the volume: docker-compose.yml.
DOCKERHOST “DOCKERHOST” specifies the daemon socket to connect to. ERROR: Couldn't connect to Docker daemon at http+docker://localunixsocket - is it running? # Don’t forget to add the port $ export DOCKERHOST=127.0.0.1:2375 What you need to know:. “DOCKERHOST” tells the client how to connect to the daemon. The default is a local socket.
This guide explains. Here’s some info on how to use it with. DOCKERMACHINENAME The “DOCKERMACHINENAME” environment variable identifies the Docker machine to run commands. $ env grep DOCKER DOCKERHOST=tcp://192.168.99.101:2376 DOCKERCERTPATH=/Users/nathanleclaire/.docker/machines/.client DOCKERTLSVERIFY=1 DOCKERMACHINENAME=dev Read this. Or, check out this from DevOps Cube. DOCKERNOWARNKERNELVERSION “DOCKERNOWARNKERNELVERSION” can be set to prevent warnings that your Linux kernel is unsuitable for Docker. # turn off kernel version warning $ export DOCKERNOWARNKERNELVERSION=1 What you need to know:.
Docker 1.11 and above do not run on kernel versions earlier than 3.4. “DOCKERNOWARNKERNELVERSION” lets users run Docker at their own risk. Check out this with info on this and other variables from Gerardnico. DOCKEROPTS “DOCKEROPTS” allows the user to set options in the Docker configuration.
# Use DOCKEROPTS to modify the daemon startup options DOCKEROPTS = '-dns 8.8.8.8 -dns 8.8.4.4' What you need to know:. “DOCKEROPTS” is often found in configuration files. Read this discussion of Here’s some from CoreOS on customizing Docker. DOCKERRAMDISK The “DOCKERRAMDISK” variable makes Docker work when root is on a ramdisk.
# tell native driver not tues pivot root $ export DOCKERRAMDISK=true What you need to know:. If set, this will disable.
If set, Docker uses “chroot.” Read this discussion of. Here’s a handy from TekSlate. DOCKERTLSVERIFY “DOCKERTLSVERIFY” enables for the local Docker client # configu export DOCKERTLSVERIFY='1' export DOCKERHOST='tcp://0.0.0.0:2376' export DOCKERCERTPATH='/etc/docker/server.pem' export DOCKERMACHINENAME=dev What you need to know:. The “DOCKERTLSVERIFY” environment variable default is unset (0). Verifies the remote. Read this discussion about. 22. DOCKERTMPDIR “DOCKERTMPDIR” sets the location for temporary Docker files.
The temporary files are created by operations such as build and load. # move the subdirectory for temporary files $ export DOCKERTMPDIR=/var/tmp What you need to know:. The default is “/var/lib/docker/tmp” Read this discussion of. 23. HOME The “HOME” variable stores the default location of Docker configuration files. # code in a Dockerfile USER developer ENV HOME /home/developer What you need to know:. “HOME” is used in a Dockerfile.
Docker sets automatically when new container is created Read this discussion about. Then, check out this list of from Nathan LeClaire. HOSTNAME “HOSTNAME” sets the hostname associated with the container. # code in a Dockerfile ENV HOSTNAME sandbox What you need to know:. “HOSTNAME” is used in a Dockerfile. Docker sets automatically when new container is created.
Read this explanation of. HTTPPROXY “HTTPPROXY” is a. If Docker is installed on a system using a corporate network using an HTTP proxy, there may be connectivity errors. # note the use of lower case ENV httpproxy ENV httpsproxy # replace with your office's proxy environment export 'HTTPPROXY=export 'HTTPSPROXY=# you can add more noproxy with your environment. Export 'NOPROXY=.example.com' What you need to know:. The “HTTPPROXY” environment variable is case sensitive. “HTTPSPROXY” takes precedence over “HTTPPROXY” for https requests Read this discussion about Here’s another helpful tutorial on.
HTTPSPROXY “HTTPSPROXY” is also a. If Docker is installed on a system using a corporate network using an HTTP proxy, there may be connectivity errors. # note the use of lower case ENV httpproxy ENV httpsproxy # replace with your office's proxy environment export 'HTTPPROXY=export 'HTTPSPROXY=# you can add more noproxy with your environment. Export 'NOPROXY=.example.com' What you need to know:. The “HTTPPROXY” environment variable is case sensitive. “HTTPSPROXY” takes precedence over “HTTPPROXY” for https requests Read this discussion about Superuser also has some helpful info about allowing.
Docker Compose Not Seeing Environment Variable On The Host Ip
JAVAHOME “JAVAHOME” is used to set the home directory of the default Java to be used. # Setting the Java version and its home directory ENV JAVAVER 8 ENV JAVAHOME /usr/lib/jvm/java-8-oracle What you need to know:. “JAVAHOME” should be set in Docker instead of letting the system pick the location automatically. Set “JAVAHOME” to the JDK root folder.
The official repository has. Read this tutorial on. JDKHOME “JDKHOME” is used to set the directory in which the Java Development Kit (JDK) is installed. # set the environment variables ENV JDKHOME /usr/lib/jvm/jdk1.8.0101 ENV JAVAHOME /usr/lib/jvm/jdk1.8.0101 ENV PATH $PATH:$JAVAHOME/bin What you need to know:. Set “JDKHOME” in Docker to the JDK root folder to make the package run faster.
Check out this documentation from Confluence on. JREHOME “JREHOME” is used to set the location of the Java Runtime Environment (JRE). # default Tomcat environment in the image for versions 7 & 8 CATALINABASE: /usr/local/tomcat CATALINAHOME: /usr/local/tomcat CATALINATMPDIR: /usr/local/tomcat/temp JREHOME: /usr CLASSPATH: /usr/local/tomcat/bin/bootstrap.jar:/usr/local/tomcat/bin/tomcat-juli.jar The “JREHOME” variable includes the location of the:. Java Virtual Machine (JVM). Java platform core classes.
Supporting Java platform libraries Read this article on, as well as on configuring this and the JAVAHOME variable on a Windows server. NAME The “NAME” environment variable sets the container name. # set the environment variable ENV NAME World What you need to know:.
If a name is not provided, Docker will generate a random name. Read this guide on the. 31. NOPROXY “NOPROXY” is a.
If Docker is installed on a system using a corporate network using an HTTP proxy, there may be connectivity errors # note the use of lower case ENV httpproxy ENV httpsproxy # replace with your office's proxy environment export 'HTTPPROXY=export 'HTTPSPROXY=# you can add more noproxy with your environment. Export 'NOPROXY=.example.com' What you need to know:. The “HTTPPROXY” environment variable is case sensitive. “HTTPSPROXY” takes precedence over “HTTPPROXY” for https requests Read this discussion about OpenShift also provides some useful on working with HTTP proxies. PATH “PATH” sets a directory on the local filesystem. # update PATH ev in Docker container ENV PATH '$PATH:/new/path' What you need to know:.
“PATH” is set automatically when a new container is created. When a relative path is set, it is relative to the location of the Compose file. Read this discussion on CloudBees also has some helpful information on inside a Docker container. TERM “TERM” needs to be set when console programs that create text-based user interfaces are used. # getting error msg TERM environment variable not set.
ENV TERM xterm What you need to know:. If the container was not started with the –tty option, then TERM needs to be manually set.
–tty sets TERM to xterm. Also, adding “ENV TERM xterm” to the Dockerfile will work. Terminals supported:.
xterm. vt220. xterm-color.
putty. konsole. Eterm. rxvt.
gnome. screen. linux.
dumb Read this discussion of. AndyK Docs offers some on this, as well. AWSACCESSKEYID “AWSACCESSKEYID” sets the access key ID for the Amazon Web Services (AWS) API. This is needed to make programmatic requests to AWS. # use flags on the command line $ docker-machine create -driver amazonec2 -amazonec2-access-key AKI.amazonec2-secret-key 8T93C. What you need to know:. The “AWSACCESSKEYID” and “AWSSECRETACCESSKEY” variables are needed to create machines on AWS. AWS access credential variables can be stored in the file /.aws/credentials Read this guide to.
Here’s another on the topic at CircleCI. AWSSECRETACCESSKEY “AWSSECRETACCESSKEY” sets the secret access key ID for the Amazon Web Services (AWS) API. This is needed to make programmatic requests to AWS.
# create during runtime docker run -e AWSACCESSKEYID=AKI.e AWSSECRETACCESSKEY=shhhhhh myimage What you need to know:. The “AWSACCESSKEYID” and “AWSSECRETACCESSKEY” environment variables are needed to create machines on AWS. AWS access credential variables can be stored in the file /.aws/credentials.
AWS does not reset or retrieve secret access keys. They need to be recreated if lost. Read this. Also, check out, a tool for encrypting and decrypting variables using KMS to support passing them to Docker containers. AWSSESSIONTOKEN “AWSSESSIONTOKEN” sets temporary credentials for an Amazon Web Services (AWS) account. # Access Key ID AWSACCESSKEYID=AKID # Secret Access Key AWSSECRETACCESSKEY=SECRET # Session Token AWSSESSIONTOKEN=TOKEN What you need to know:. “AWSSESSIONTOKEN” is not required to be set.
AWS access credential variables can be stored in the file /.aws/credentials. Temporary credentials are valid from 15 minutes to 36 hours.
Default: 12 hours. Read this. also offers some useful information on playing with variables. AWSAMI “AWSAMI” returns the Amazon Machine Image (AMI). Export AWSAMI=ami-5189a661 #Ubuntu Server 14.04 LTS (HVM) What you need to know:. Only the default Docker AWS AMI is supported. “AWSAMI” refers to a virtual machine image.
The default SSH username for the default AMIs is ubuntu. Read this discussion of. Also, check out Yevgeniy Brikman’s in-depth tutorial on from the ground-up. AWSDEFAULTREGION “AWSDEFAULTREGION” sets where to make Amazon Web Services (AWS) calls against.
This is usually the region closest to you, but it can be any region. # set configuration export AWSACCESSKEYID='TBD' export AWSSECRETACCESSKEY='TBD' export AWSDEFAULTREGION='eu-west-1' What you need to know:. The “AWSDEFAULTREGION” default is “us-east-1.”. Available regions are:. ap-northeast-1 (ami-b36d4edd). ap-southeast-1 (ami-1069af73).
ap-southeast-2 (ami-1d336a7e). ca-central-1 (ami-ca6ddfae).
cn-north-1 (ami-79eb2214). eu-west-1 (ami-8aa67cf9).
eu-central-1 (ami-ab0210c7). sa-east-1 (ami-185de774). us-east-1 (ami-26d5af4c). us-west-1 (ami-9cbcd2fc). us-west-2 (ami-16b1a077). us-gov-west-1 (ami-b0bad893) See the. AWSVPCID “AWSVPCID” sets the name of the virtual private cloud (VPC) dedicated to the Amazon Web Services (AWS) account.
# set configuration $ export AWSSECRETACCESSKEY=xxxxxxxxxxx $ export AWSACCESSKEYID=yyyyyyyyyy $ export AWSVPCID=vpc-12345678 Read this. Check out on getting started with Docker Machine on Amazon EC2. AWSZONE “AWSZONE” sets the Amazon Web Services (AWS) availability zone to set the instance in. Availability zones are distinct locations that are engineered to be isolated from failures in other availability zones.
# create container export AWSACCESSKEYID export AWSSECRETACCESSKEY export AWSDEFAULTREGION=ap-northeast-1 export AWSZONE=a export AWSSUBNETID export AWSINSTANCETYPE=c4.large export AWSSECURITYGROUP What you need to know:. The “AWSZONE” default is a. AWS independently maps availability zones to identifiers for each account. Read this. Also, you might find from PromptWorks on handling environment secrets in Docker on the AWS container service helpful.
AWSSUBNETID “AWSSUBNETID” identifies the Amazon Web Services (AWS) virtual private cloud (VPC) subnet ID. # create container export AWSACCESSKEYID export AWSSECRETACCESSKEY export AWSDEFAULTREGION=ap-northeast-1 export AWSZONE=a export AWSSUBNETID export AWSINSTANCETYPE=c4.large export AWSSECURITYGROUP What you need to know:. Each subnet resides entirely within one availability zone and cannot span zones. Read this. Also, check out on Medium about using Docker and AWS for a better dev/test experience. AWSSECURITYGROUP “AWSSECURITYGROUP” identifies the Amazon Web Services (AWS) virtual private cloud (VPC) security group name.
# create container export AWSACCESSKEYID export AWSSECRETACCESSKEY export AWSDEFAULTREGION=ap-northeast-1 export AWSZONE=a export AWSSUBNETID export AWSINSTANCETYPE=c4.large export AWSSECURITYGROUP What you need to know:. The “AWSSECURITYGROUP” default is docker-machine. The security group will be associated to the host. Following ports will be opened inbound:. ssh (22/tcp). docker (2376/tcp).
swarm (3376/tcp), only if the node is a swarm master Read this guide to. 43. AWSTAGS “AWSTAGS” sets the Amazon Web Services (AWS) tag key-value pairs that can be passed with the instance provisioning. # tags to use awstags key1,value1,key2,value2 What you need to know:.
“AWSTAGS” separates keys and values by comma. The tags are stored as strings. Read this. 44. AWSINSTANCEPROFILE “AWSINSTANCEPROFILE” sets the Amazon Web Services (AWS) IAM role name to be used as the instance profile. # create container export AWSACCESSKEYID export AWSSECRETACCESSKEY export AWSDEFAULTREGION=ap-northeast-1 export AWSZONE=a export AWSINSTANCEPROFILE export AWSINSTANCETYPE=c4.large export AWSSECURITYGROUP What you need to know:.
AWS Identity and Access Management (IAM) is a feature that manages users and their access to AWS resources. IAM role credentials automatically rotate about every 15 minutes. This prevents stolen credentials from being valid for long. Read this. Lyft Engineering also provides some information on scoping AWS IAM roles to Docker containers in this. AWSINSTANCETYPE “AWSINSTANCETYPE” specifies the instance type to run. # create machine “aws-test” docker-machine create -d amazonec2 -amazonec2-region us-west-2 -amazonec2-instance-type 't2.micro' -amazonec2-ssh-keypath /.ssh/sshkey aws-test What you need to know:. The “AWSINSTANCETYPE” Docker environment variable defaults to t2.micro.
The instance type refers to the hardware configuration that determines resources available. Check this. 46. AWSDEVICENAME The “AWSDEVICENAME” variable specifies the EBS volume name to be attached to the instance. # set up instance $ export AWSAMI='ami-11c57862' $ export AWSDEFAULTREGION='eu-west-1' $ export AWSDEVICENAME='/dev/xvda' $ export AWSINSTANCETYPE='t2.small' $ export AWSSSHUSER='admin' What you need to know:.
“AWSDEVICENAME” defaults to /dev/sda1. Read this discussion about. 47. AWSROOTSIZE “AWSROOTSIZE” specifies the size of the disk to be attached to the instance in gigabytes. # default values used for EC2 instances AWSINSTANCETYPE=t2.micro AWSROOTSIZE=16 What you need to know:.
“AWSROOTSIZE” defaults to 16 gigabytes. Read this. 48. AWSVOLUMETYPE “AWSVOLUMETYPE” specifies the Amazon EBS volume type to be attached to the instance.
# default values AWSINSTANCETYPE=t2.micro AWSROOTSIZE=16 AWSVOLUMETYPE= gp2 What you need to know:. “AWSVOLUMETYPE” defaults to gp2. The Amazon EBS volume types available:. gp2 — General purpose solid-state drive. io1 — High performance solid state drive.
st1 — Frequently accessed hard disk drive. sc1 — Less frequently accessed hard disk drive.
Read this. 49. AWSSSHUSER “AWSSSHUSER” specifies the SSH Login username. # set up configuration export AWSAMI='ami-971a65e0' export AWSDEFAULTREGION='eu-west-1' export AWSVPCID='vpc-69c9a10c' export AWSINSTANCETYPE='t1.micro' export AWSSSHUSER='admin' What you need to know:. The “AWSSSHUSER” Docker environment variable is ubuntu.
“AWSSSHUSER” must match the default SSH user set in the AMI used. Read this. 50. AWSSSHKEYPATH “AWSSSHKEYPATH” specifies the path to the SSH private key file to use for the instance. # where to find the SSH key file export AWSSSHKEYPATH = /.ssh/sshkey What you need to know:. If “AWSSSHKEYPATH” is not specified, Docker Machine will generate a new key for the current instance. Matching public key with.pub extension should exist. Read this. Here’s some additional information on from Docker.
What variables do you use most to set up and configure server applications? Share your thoughts with us in the comments below.