Quero mudar para o Docker, então comecei a mexer com isso. Instalei o Docker em uma instalação do VirtualBox Ubuntu 15.10 (Wily Werewolf) e, conforme sugerido aqui , tentei executar um nginx básico Docker:
$ docker run --name mynginx1 -P -d nginx
Cannot connect to the Docker daemon. Is the docker daemon running on this host?
Então, verifiquei se o Docker estava em execução:
$ sudo service docker status
● docker.service - Docker Application Container Engine
Loaded: loaded (/lib/systemd/system/docker.service; enabled; vendor preset: enabled)
Active: active (running) since vr 2015-11-06 08:41:48 CET; 15min ago
Docs: https://docs.docker.com
Main PID: 7542 (docker)
CGroup: /system.slice/docker.service
└─7542 /usr/bin/docker daemon -H fd://
nov 06 08:41:47 kramer65-VirtualBox systemd[1]: Starting Docker Application Container Engine...
nov 06 08:41:47 kramer65-VirtualBox docker[7542]: time="2015-11-06T08:41:47.900410966+01:00" level=info msg="API ...ock"
nov 06 08:41:48 kramer65-VirtualBox docker[7542]: time="2015-11-06T08:41:48.033514149+01:00" level=info msg="Fire...lse"
nov 06 08:41:48 kramer65-VirtualBox docker[7542]: time="2015-11-06T08:41:48.141594321+01:00" level=info msg="Defa...ess"
nov 06 08:41:48 kramer65-VirtualBox docker[7542]: time="2015-11-06T08:41:48.416294436+01:00" level=warning msg="Y...it."
nov 06 08:41:48 kramer65-VirtualBox docker[7542]: time="2015-11-06T08:41:48.565507576+01:00" level=info msg="Load...rt."
nov 06 08:41:48 kramer65-VirtualBox docker[7542]: time="2015-11-06T08:41:48.567907022+01:00" level=info msg="Load...ne."
nov 06 08:41:48 kramer65-VirtualBox docker[7542]: time="2015-11-06T08:41:48.567945214+01:00" level=info msg="Daem...ion"
nov 06 08:41:48 kramer65-VirtualBox docker[7542]: time="2015-11-06T08:41:48.567969891+01:00" level=info msg="Dock....9.0
nov 06 08:41:48 kramer65-VirtualBox systemd[1]: Started Docker Application Container Engine.
Hint: Some lines were ellipsized, use -l to show in full.
Isso sugere que o daemon do Docker já está em execução, mas para ter certeza de que iniciei o daemon do Docker manualmente:
$ sudo docker daemon
INFO[0000] API listen on /var/run/docker.sock
INFO[0000] [graphdriver] using prior storage driver "aufs"
INFO[0000] Firewalld running: false
INFO[0000] Default bridge (docker0) is assigned with an IP address XXX.XX.X.X/XX. Daemon option --bip can be used to set a preferred IP address
WARN[0000] Your kernel does not support swap memory limit.
INFO[0000] Loading containers: start.
INFO[0000] Loading containers: done.
INFO[0000] Daemon has completed initialization
INFO[0000] Docker daemon commit=76d6bc9 execdriver=native-0.2 graphdriver=aufs version=1.9.0
Tentei executar a imagem novamente, mas com o mesmo resultado:
$ docker run --name mynginx1 -P -d nginx
Cannot connect to the Docker daemon. Is the docker daemon running on this host?
Eu tentei executar o comando, mas sem sucesso. O que eu estou fazendo errado aqui?