What is the version of Docker Server Engine running on the Host?

$ docker version Client: Docker Engine - Community Version: 20.10.24 API version: 1.41 Go version: go1.19.7 Git commit: 297e128 Built: Tue Apr 4 18:21:05 2023 OS/Arch: linux/amd64 Context: default Experimental: true Server: Docker Engine - Community Engine: Version: 20.10.24

How many containers are running on this host?

$ docker ps CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES

How many images are available on this host?

$ docker image ls REPOSITORY TAG IMAGE ID CREATED SIZE redis latest eca1379fe8b5 5 months ago 117MB mysql latest 8189e588b0e8 5 months ago 564MB nginx latest 6efc10a0510f 5 months ago 142MB postgres latest ceccf204404e 5 months ago 379MB nginx alpine 8e75cbc5b25c 5 months ago 41MB alpine latest 9ed4aefc74f6 5 months ago 7.04MB ubuntu latest 08d22c0ceb15 6 months ago 77.8MB kodekloud/simple-webapp-mysql latest 129dd9f67367 4 years ago 96.6MB kodekloud/simple-webapp latest c6e3cd9aae36 4 years ago 84.8MB

Run a container using the redis image

$ docker run redis 1:C 24 Sep 2023 12:43:53.333 # oO0OoO0OoO0Oo Redis is starting oO0OoO0OoO0Oo 1:C 24 Sep 2023 12:43:53.333 # Redis version=7.0.11, bits=64, commit=00000000, modified=0, pid=1, just started 1:C 24 Sep 2023 12:43:53.333 # Warning: no config file specified, using the default config. In order to specify a config file use redis-server /path/to/redis.conf 1:M 24 Sep 2023 12:43:53.334 * monotonic clock: POSIX clock_gettime 1:M 24 Sep 2023 12:43:53.338 * Running mode=standalone, port=6379. 1:M 24 Sep 2023 12:43:53.338 # Server initialized

Stop the container you just created

$ docker container stop redis

How many containers are RUNNING on this host now?

$ docker container ls CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 328767d33822 alpine "sleep 1000" 28 seconds ago Up 26 seconds priceless_noether 26a04b0207ab nginx:alpine "/docker-entrypoint.…" 30 seconds ago Up 28 seconds 80/tcp nginx-2 ad931ecf7142 nginx:alpine "/docker-entrypoint.…" 33 seconds ago Up 30 seconds 80/tcp nginx-1 8b4374345f28 ubuntu "sleep 1000" 36 seconds ago Up 32 seconds awesome_northcut

How many containers are PRESENT on the host now? Including both Running and Not Running ones

$ docker container ls -a CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 829529f8f010 alpine "/bin/sh" About a minute ago Exited (0) About a minute ago zen_boyd 328767d33822 alpine "sleep 1000" About a minute ago Up About a minute priceless_noether 26a04b0207ab nginx:alpine "/docker-entrypoint.…" About a minute ago Up About a minute 80/tcp nginx-2 ad931ecf7142 nginx:alpine "/docker-entrypoint.…" About a minute ago Up About a minute 80/tcp nginx-1 8b4374345f28 ubuntu "sleep 1000" About a minute ago Up About a minute awesome_northcut 4db07af9ad0f redis "docker-entrypoint.s…" 3 minutes ago Exited (0) 2 minutes ago nervous_haibt

What is the image used to run the nginx-1 container?

$ docker container ls -a CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 829529f8f010 alpine "/bin/sh" 5 minutes ago Exited (0) 5 minutes ago zen_boyd 328767d33822 alpine "sleep 1000" 5 minutes ago Up 5 minutes priceless_noether 26a04b0207ab nginx:alpine "/docker-entrypoint.…" 5 minutes ago Up 5 minutes 80/tcp nginx-2 ad931ecf7142 nginx:alpine "/docker-entrypoint.…" 5 minutes ago Up 5 minutes 80/tcp nginx-1 8b4374345f28 ubuntu "sleep 1000" 5 minutes ago Up 5 minutes awesome_northcut 4db07af9ad0f redis "docker-entrypoint.s…" 7 minutes ago Exited (0) 6 minutes ago nervous_haibt

What is the name of the container created using the ubuntu image?

$ docker container ls -a CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 829529f8f010 alpine "/bin/sh" 5 minutes ago Exited (0) 5 minutes ago zen_boyd 328767d33822 alpine "sleep 1000" 5 minutes ago Up 5 minutes priceless_noether 26a04b0207ab nginx:alpine "/docker-entrypoint.…" 6 minutes ago Up 5 minutes 80/tcp nginx-2 ad931ecf7142 nginx:alpine "/docker-entrypoint.…" 6 minutes ago Up 6 minutes 80/tcp nginx-1 8b4374345f28 ubuntu "sleep 1000" 6 minutes ago Up 6 minutes awesome_northcut 4db07af9ad0f redis "docker-entrypoint.s…" 8 minutes ago Exited (0) 7 minutes ago nervous_haibt

What is the ID of the container that uses the alpine image and is not running?

$ docker container ls -a | grep 'alpine' | grep 'Exited' 829529f8f010 alpine "/bin/sh" 8 minutes ago Exited (0) 8 minutes ago zen_boyd

Delete all containers from the Docker Host. Both Running and Not Running ones. Remember you may have to stop containers before deleting them.

$ docker ps -aq 829529f8f010 328767d33822 26a04b0207ab ad931ecf7142 8b4374345f28 4db07af9ad0f Then, start removing $ docker rm $(docker ps -aq) --force 328767d33822 26a04b0207ab ad931ecf7142 8b4374345f28

Delete the ubuntu Image.

$ docker image rm ubuntu Untagged: ubuntu:latest Untagged: ubuntu@sha256:67211c14fa74f070d27cc59d69a7fa9aeff8e28ea118ef3babc295a0428a6d21 Deleted: sha256:08d22c0ceb150ddeb2237c5fa3129c0183f3cc6f5eeb2e7aa4016da3ad02140a Deleted: sha256:b93c1bd012ab8fda60f5b4f5906bf244586e0e3292d84571d3abb56472248466

You are required to pull a docker image which will be used to run a container later. Pull the image nginx:1.14-alpine Only pull the image, do not create a container.

$ docker pull nginx:1.14-alpine 1.14-alpine: Pulling from library/nginx bdf0201b3a05: Pull complete 3d0a573c81ed: Pull complete 8129faeb2eb6: Pull complete 3dc99f571daf: Pull complete Digest: sha256:485b610fefec7ff6c463ced9623314a04ed67e3945b9c08d7e53a47f6d108dc7 Status: Downloaded newer image for nginx:1.14-alpine docker.io/library/nginx:1.14-alpine

Run a container with the nginx:1.14-alpine image and name it webapp

$ docker run -d --name webapp nginx:1.14-alpine b6e0ced33b70b8e8e93f2cc4ec1b4e1c40c43d6a57ceb563d0d6572c4b233203

Cleanup: Delete all images on the host Remove containers as necessary

$ docker image ls -aq #to see all container images eca1379fe8b5 8189e588b0e8 6efc10a0510f ceccf204404e 8e75cbc5b25c 9ed4aefc74f6 8a2fb25a19f5 129dd9f67367 c6e3cd9aae36 $ docker image rm $(docker image ls -aq) --force #to delete all container images

Let us first inspect the environment. How many containers are running on this host?

$ docker container ls CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES d5259591611a nginx:alpine "/docker-entrypoint.…" 26 seconds ago Up 24 seconds 0.0.0.0:3456->3456/tcp, 0.0.0.0:38080->80/tcp vigorous_keller

What is the image used by the container?

$ docker container ls CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES d5259591611a nginx:alpine "/docker-entrypoint.…" 26 seconds ago Up 24 seconds 0.0.0.0:3456->3456/tcp, 0.0.0.0:38080->80/tcp vigorous_keller

How many ports are published on this container?

$ docker inspect $(docker container ls -aq) "Ports": { "3456/tcp": [ { "HostIp": "0.0.0.0", "HostPort": "3456" } ], "80/tcp": [ { "HostIp": "0.0.0.0", "HostPort": "38080" } ] },

Run an instance of kodekloud/simple-webapp with a tag blue and map port 8080 on the container to 38282 on the host.

$ docker run -d -p 38282:8080 kodekloud/simple-webapp:blue Unable to find image 'kodekloud/simple-webapp:blue' locally blue: Pulling from kodekloud/simple-webapp 4fe2ade4980c: Already exists 7cf6a1d62200: Already exists f0d690b9e495: Already exists fac5d45ad062: Already exists a6fc8a0deb7d: Pull complete f43c8e496f88: Pull complete 58ca939f7651: Pull complete 095a1a007cdb: Pull complete Digest: sha256:9caf15476dc60b77c7460791bea8ea5f6ca02b90199aabe088beea83bc943fe5 Status: Downloaded newer image for kodekloud/simple-webapp:blue a9707f4ce8e31553d2f7c99436a155b33b18e83d92f92ff2bf95905d2e9ff0e9

How many images are available on this host?

$ docker image ls REPOSITORY TAG IMAGE ID CREATED SIZE redis latest eca1379fe8b5 5 months ago 117MB mysql latest 8189e588b0e8 5 months ago 564MB nginx latest 6efc10a0510f 5 months ago 142MB postgres latest ceccf204404e 5 months ago 379MB nginx alpine 8e75cbc5b25c 5 months ago 41MB alpine latest 9ed4aefc74f6 5 months ago 7.04MB ubuntu latest 08d22c0ceb15 6 months ago 77.8MB kodekloud/simple-webapp-mysql latest 129dd9f67367 4 years ago 96.6MB kodekloud/simple-webapp latest c6e3cd9aae36 4 years ago 84.8MB

How many images are available on this host?

$ docker image ls REPOSITORY TAG IMAGE ID CREATED SIZE ubuntu latest 08d22c0ceb15 6 months ago 77.8MB

We just pulled a new image. What is the tag on the newly pulled NGINX image?

$ docker image ls REPOSITORY TAG IMAGE ID CREATED SIZE nginx 1.14-alpine 8a2fb25a19f5 4 years ago 16MB

We just downloaded the code of an application. What is the base image used in the Dockerfile? Inspect the Dockerfile in the webapp-color directory.

$ cat webapp-color/Dockerfile FROM python:3.6 RUN pip install flask COPY . /opt/ EXPOSE 8080 WORKDIR /opt ENTRYPOINT ["python", "app.py"]

When a container is created using the image built with this Dockerfile, what is the command used to RUN the application inside it. Inspect the Dockerfile in the webapp-color directory.

$ cat webapp-color/Dockerfile FROM python:3.6 RUN pip install flask COPY . /opt/ EXPOSE 8080 WORKDIR /opt ENTRYPOINT ["python", "app.py"]

What port is the web application run within the container? Inspect the Dockerfile in the webapp-color directory.

$ cat webapp-color/Dockerfile FROM python:3.6 RUN pip install flask COPY . /opt/ EXPOSE 8080 WORKDIR /opt ENTRYPOINT ["python", "app.py"]

Build a docker image using the Dockerfile and name it webapp-color. No tag to be specified.

$ docker build -t webapp-color webapp-color

Run an instance of the image webapp-color and publish port 8080 on the container to 8282 on the host.

$ docker container run -d -p 8282:8080 webapp-color e9bf9501626e9542b5839af930fb5b7441b537b1cdc727f2f7598c4cc87e065b

What is the approximate size of the webapp-color image?

$ docker image ls | grep "webapp-color" webapp-color latest e742f4d8648f 6 minutes ago 913MB

Build a new smaller docker image by modifying the same Dockerfile and name it webapp-color and tag it lite. Hint: Find a smaller base image for python:3.6. Make sure the final image is less than 150MB.

$ cat Dockerfile #first change python to python:3.6-alpine FROM python:3.6-alpine RUN pip install flask COPY . /opt/ EXPOSE 8080 WORKDIR /opt ENTRYPOINT ["python", "app.py"] $ docker build -t webapp-color:lite .

Run an instance of the new image webapp-color:lite and publish port 8080 on the container to 8383 on the host.

$ docker container run -d -p 8383:8080 webapp-color:lite 52464d475fce40cf6bf972331643e3a065d587f57bbcb8497e688435f520d801

Inspect the environment variables set on the running container and identify the value set to the APP_COLOR variable.

$ docker container ls CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 0985f8303d49 kodekloud/simple-webapp "python app.py" 14 seconds ago Up 13 seconds 8080/tcp epic_panini $ docker inspect 0985f8303d49 "Env": [ "APP_COLOR=pink", "PATH=/usr/local/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin", "LANG=C.UTF-8", "GPG_KEY=0D96DF4D4110E5C43FBFB17F2D347EA6AA65421D", "PYTHON_VERSION=3.6.6", "PYTHON_PIP_VERSION=18.1" ],

Run a container named blue-app using image kodekloud/simple-webapp and set the environment variable APP_COLOR to blue. Make the application available on port 38282 on the host. The application listens on port 8080.

$ docker container run -d -p 38282:8080 --name blue-app -e APP_COLOR=blue kodekloud/simple-webapp 909e0479992e0c2572aabefde7a2c617c4bccb5f766b592f627598bb6f5d203c

Deploy a mysql database using the mysql image and name it mysql-db. Set the database password to use db_pass123. Lookup the mysql image on Docker Hub and identify the correct environment variable to use for setting the root password.

$ docker container run -d --name mysql-db -e MYSQL_ROOT_PASSWORD=db_pass123 mysql d46c3ef826477c53c1dd101aaf063997596dbedab79759b152f026518f8d9023

What is the ENTRYPOINT configured on the mysql image?

$ cat Dockerfile-mysql | grep "ENTRYPOINT" ENTRYPOINT ["docker-entrypoint.sh"]

What is the CMD configured on the wordpress image?

$ cat Dockerfile-wordpress | grep "CMD" CMD ["apache2-foreground"]

What is the final command run at startup when the wordpress image is run. Consider both ENTRYPOINT and CMD instructions

$ cat Dockerfile-wordpress | grep "CMD" CMD ["apache2-foreground"] $ cat Dockerfile-wordpress | grep "ENTRYPOINT" ENTRYPOINT ["docker-entrypoint.sh"]

What is the command run at startup when the ubuntu image is run?

$ cat Dockerfile-ubuntu | grep "CMD" CMD ["bash"]

Run an instance of the ubuntu image to run the sleep 1000 command at startup. Run it in detached mode.

$ docker container run -d --name ubuntu-sleeper ubuntu sleep 1000 78dbf2c180aa5e9c0e4ba96b3e26cbf5c6a30fd48d1a501b775f10905d06ff29

First create a redis database container called redis, image redis:alpine. if you are unsure, check the hints section for the exact commands.

$ docker container run -d --name redis redis:alpine Unable to find image 'redis:alpine' locally alpine: Pulling from library/redis 7264a8db6415: Pull complete a28817da73be: Pull complete 536ccaebaffb: Pull complete cf393c8f1348: Pull complete e450001ba352: Pull complete e704b26e22f6: Pull complete Digest: sha256:ef3296cb1b3a7eb40f2a992a398777a1c0b5b21df44f1a5bef84067f772daf54 Status: Downloaded newer image for redis:alpine 5fb03179f382ca6b4be74979fbbc21e6d9d9a81b91a2bb9c90b93fa5845fdea9

Next, create a simple container called clickcounter with the image kodekloud/click-counter, link it to the redis container that we created in the previous task and then expose it on the host port 8085 The clickcounter app run on port 5000. if you are unsure, check the hints section for the exact commands.

$ docker container run -d --name clickcounter --link redis -p 8085:5000 kodekloud/click-counter Unable to find image 'kodekloud/click-counter:latest' locally latest: Pulling from kodekloud/click-counter 540db60ca938: Pull complete a7ad1a75a999: Pull complete 37ce6546d5dd: Pull complete ec9e91bed5a2: Pull complete 767433e10bb0: Pull complete 156f0b0493cb: Pull complete 3fe82d8a2401: Pull complete 4a41f7c94204: Pull complete 473063430a4f: Pull complete 452c68a16ccd: Pull complete Digest: sha256:530e4532a718e8f5cbda05844a6c0638ebe8898fa4c4307ee6afbdd5d1f213db Status: Downloaded newer image for kodekloud/click-counter:latest 0d43e082c6dd996ade594ca34d639e48288c3c1dc962c418dbff97e32adeca24

Let's clean up the actions carried out in previous steps. Delete the redis and the clickcounter containers.

$ docker container ls -aq 0d43e082c6dd 5fb03179f382 $ docker container rm $(docker container ls -aq) --force 0d43e082c6dd 5fb03179f382

Create a docker-compose.yml file under the directory /root/clickcounter. Once done, run docker-compose up. The compose file should have the exact specification as follows - redis service specification - Image name should be redis:alpine. clickcounter service specification - Image name should be kodekloud/click-counter, app is run on port 5000 and expose it on the host port 8085 in the compose file.

$ cd /root/clickcounter # we change directory to /root/clickcounter $ pwd /root/clickcounter $ touch docker-compose.yml # we create docker-compose.yml file $ ls docker-compose.yml $ vim docker-compose.yml # we edit docker-compose.yml file $ cat docker-compose.yml version: '3.8' services: redis: image: redis:alpine clickcounter: image: kodekloud/click-counter ports: - '8085:5000' $ docker-compose up

What location are the files related to the docker containers and images stored?

$ docker info | grep "Docker Root Dir" Docker Root Dir: /var/lib/docker

What directory under /var/lib/docker are the files related to the container alpine-3 image stored?

$ docker inspect alpine-3 | grep "Id" "Id": "48a7de550f6268d17c818745496fd1b92a9f3093371a096ded04997b7cc4dcbd",

Run a mysql container named mysql-db using the mysql image. Set database password to db_pass123 Note: Remember to run it in the detached mode.

$ docker container run -d --name mysql-db -e MYSQL_ROOT_PASSWORD=db_pass123 mysql 6ddc029815318be19ff41fdbb1521c9a9d0980e71556428ebf8245915800b3d0

We have just written some data into the database. To view the information we wrote, run the get-data.sh bash available in the /root directory. How many customers data have been written to the database? Command: sh get-data.sh

$ sh get-data.sh

Run a mysql container again, but this time map a volume to the container so that the data stored by the container is stored at /opt/data on the host. Use the same name : mysql-db and same password: db_pass123 as before. Mysql stores data at /var/lib/mysql inside the container.

$ docker container run -d --name mysql-db -e MYSQL_ROOT_PASSWORD=db_pass123 -v /opt/data:/var/lib/mysql mysql 79791c6d80eae988dbf0775d462373eaa822a2072b05f7ea8e8ce9cc9189f327

Explore the current setup and identify the number of networks that exist on this system.

$ docker network ls NETWORK ID NAME DRIVER SCOPE 5b1e25ce69bc bridge bridge local e1bd4eeb89ea host host local cc017d20d8c9 none null local

What is the ID associated with the bridge network?

$ docker network ls | grep "bridge" 5b1e25ce69bc bridge bridge local

We just ran a container named alpine-1. Identify the network it is attached to.

$ docker network ls NETWORK ID NAME DRIVER SCOPE 5b1e25ce69bc bridge bridge local e1bd4eeb89ea host host local cc017d20d8c9 none null local $ docker inspect alpine-1 | grep "NetworkID" # we understand that alpine-1 is attached to host network "NetworkID": "e1bd4eeb89ea00d56f811c10a01bc5a672bcf1487b483acee53a406886b29b21",

What is the subnet configured on bridge network?

$ docker network inspect bridge | grep "Subnet" "Subnet": "172.12.0.0/24",

Run a container named alpine-2 using the alpine image and attach it to the none network.

$ docker container run -d --name alpine-2 --network none alpine dd6691d699b95c2b1ca051f20f3f18b8352551b9ffef63902c687dd77791bcbc

Create a new network named wp-mysql-network using the bridge driver. Allocate subnet 182.18.0.1/24. Configure Gateway 182.18.0.1

$ docker network create --driver bridge --subnet 182.18.0.1/24 --gateway 182.18.0.1 wp-mysql-network a6a6574721bfd925fc773ffb7f73b5f2a2588ec713e8d282e5d0962687be87e5

Deploy a mysql database using the mysql:5.6 image and name it mysql-db. Attach it to the newly created network wp-mysql-network Set the database password to use db_pass123. The environment variable to set is MYSQL_ROOT_PASSWORD.

$ docker container run -d --name mysql-db -e MYSQL_ROOT_PASSWORD=db_pass123 --network wp-mysql-network mysql:5.6 Unable to find image 'mysql:5.6' locally 5.6: Pulling from library/mysql 35b2232c987e: Pull complete fc55c00e48f2: Pull complete 0030405130e3: Pull complete e1fef7f6a8d1: Pull complete 1c76272398bb: Pull complete f57e698171b6: Pull complete f5b825b269c0: Pull complete dcb0af686073: Pull complete 27bbfeb886d1: Pull complete 6f70cc868145: Pull complete 1f6637f4600d: Pull complete Digest: sha256:20575ecebe6216036d25dab5903808211f1e9ba63dc7825ac20cb975e34cfcae Status: Downloaded newer image for mysql:5.6 6e7a55afd542f8470303dc30ba91d6b11544911322e51f43ca10bdfcdc585f68

Deploy a web application named webapp using the kodekloud/simple-webapp-mysql image. Expose the port to 38080 on the host. The application makes use of two environment variable: 1: DB_Host with the value mysql-db. 2: DB_Password with the value db_pass123. Make sure to attach it to the newly created network called wp-mysql-network. Also make sure to link the MySQL and the webapp container.

$ docker container run -d --name webapp -e DB_Host=mysql-db -e DB_Password=db_pass123 --network wp-mysql-network -p 38080 kodekloud/simple-webapp-mysql 5d6d011373c376944f313d768296c806397a84176be982f61834b1c40a24f88d