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Docker Quickstart Guide

frank — Tue, 10 Apr 2018 17:56:02 +0000

Glossary

host => the real machine
container => inside host

Start Docker

Docker won't run by default after reboot.

sudo systemctl start docker

Verify that docker is installed correctly by running the hello-world image.

sudo docker run hello-world

List Existing Docker Images

docker image ls

It will return a list like this (if you have use it for a while)

REPOSITORY                    TAG                           IMAGE ID       CREATED         SIZE
selenium/standalone-chrome    latest                        09fb5857c74e   19 months ago   857MB
hello-world                   latest                        fce289e99eb9   23 months ago   1.84kB
calypso_vfcore-build          latest                        5b4730e3fbb1   2 years ago     929MB
libcerblicense-build          latest                        c7a73702b1e5   2 years ago     386MB
libcerb-build                 latest                        97deac334875   2 years ago     753MB
hmp-orthrus-build             calypso_os_base_build-cent6   de60aedbbd82   2 years ago     1.04GB
calypso_native-build          latest                        3467195ffe10   2 years ago     1.25GB
calypso_js-build              latest                        ad6cec0db18a   2 years ago     1.11GB
calypso_www-build             latest                        0bb30e97f177   2 years ago     1.49GB
calypso_os_base_build         cent6                         a9442bf2d72f   2 years ago     929MB
calypso_os_base_build         cent7                         426ad4aadad9   2 years ago     1.44GB
calypso_tc-fetch              latest                        3ac23b723553   2 years ago     931MB
centos                        6                             b5e5ffb5cdea   2 years ago     194MB
centos                        7                             5182e96772bf   2 years ago     200MB
python                        3                             825141134528   2 years ago     923MB
cdvrdeva12a0a98_backend       latest                        77428cfac8c4   2 years ago     3.12GB
cdvr-rpm-centos7              latest                        507dbd91a5d2   2 years ago     1.32GB
madra-rpm-centos7             latest                        a909b8b8b02e   2 years ago     814MB
cdvrdeva12a0a98_backend-gdb   latest                        3f05e146c10f   2 years ago     4.68GB
cdvrdeva12a0a98_frontend      latest                        e99f83b6f20e   2 years ago     1.98GB
cdvrdeva12a0a98_nightwatch    latest                        e0bd9f226bd8   2 years ago     3.12GB
cdvrdeva12a0a98_mongod        latest                        fc40335a2f52   2 years ago     2.26GB
cdvrdeva12a0a98_mongo         latest                        fc40335a2f52   2 years ago     2.26GB
cdvr-dev-base                 a12a0a98                      aafceed8649d   2 years ago     1.98GB
centos                        centos7                       49f7960eb7e4   2 years ago     200MB
ownyourbits/minidebian        latest                        50e95dd30fa1   3 years ago     58.1MB

Delete All Docker Images

WARNING !! it will really delete them...

docker image ls -q | xargs -I {} docker image rm -f {}

Note: It might not delete some with child-parent dependencies where one needs to be deleted first. Re-run "docker image ls" to see if all are deleted.

Open a shell to the docker

docker exec -i -t  /bin/bash

Upload files to container

Method 1 - Use shared volumes

Method 2 - Docker copy

Shared Volumes

docker inspect kraken

The post Docker Quickstart Guide appeared first on Techy Things.

Cannot connect to the Docker daemon. Is 'docker daemon' running on this host?: dial unix /var/run/docker.sock: connect: permission denied

frank — Tue, 10 Apr 2018 15:13:59 +0000

ERRO[0000] failed to dial gRPC: cannot connect to the Docker daemon. Is 'docker daemon' running on this host?: dial unix /var/run/docker.sock: connect: permission denied
Got permission denied while trying to connect to the Docker daemon socket at unix:///var/run/docker.sock

Solution

$> sudo usermod -aG docker

$> reboot

$> sudo systemctl start docker

$> sudo docker run hello-world

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ERROR: Couldn't connect to Docker daemon at http+docker://localunixsocket - is it running?

frank — Wed, 21 Feb 2018 22:08:30 +0000

+ docker-compose -f /home/dev/cal7/vfcore/calypso/docker/build/docker-compose.yaml stop tc-fetch
WARNING: The HAI_BASEOS variable is not set. Defaulting to a blank string.
ERROR: Couldn't connect to Docker daemon at http+docker://localunixsocket - is it running?

If it's at a non-standard location, specify the URL with the DOCKER_HOST environment variable.


[dev@baobab docker]$ docker version
Client version: 1.7.1
Client API version: 1.19
Go version (client): go1.4.2
Git commit (client): 786b29d/1.7.1
OS/Arch (client): linux/amd64
Get http:///var/run/docker.sock/v1.19/version: dial unix /var/run/docker.sock: permission denied. Are you trying to connect to a TLS-enabled daemon without TLS?

[dev@baobab docker]$ sudo docker version
Client version: 1.7.1
Client API version: 1.19
Go version (client): go1.4.2
Git commit (client): 786b29d/1.7.1
OS/Arch (client): linux/amd64
Server version: 1.7.1
Server API version: 1.19
Go version (server): go1.4.2
Git commit (server): 786b29d/1.7.1
OS/Arch (server): linux/amd64

Solution

[dev@baobab docker]$ sudo groupadd docker
(Note: In most case this group will already exists, safely ignore the message)
[dev@baobab docker]$ sudo usermod -aG docker ${USER}

and reboot (Important!)

The post ERROR: Couldn't connect to Docker daemon at http+docker://localunixsocket - is it running? appeared first on Techy Things.