https://blog.geekhunter.com.br/docker-na-pratica-como-construir-uma-aplicacao/
Cgroup:
Systemd : (container with systemd) https://wiki.archlinux.org/index.php/systemd-nspawn#Create_a_Debian_or_Ubuntu_environment
https://docs.docker.com/develop/develop-images/dockerfile_best-practices/
Lembre-se que de incluir o systemd ou upstart, pois eles gerenciam os processos, então se um processo comer mais memoria do que tem, o processo pode morrer. Exemplo em cgroup aulas William ;)
Na máquina fonte:
# docker commit <nome-ou-id-container> <nome-nova-imagem>
# docker save <nome-nova-imagem> > /tmp/nome-nova-imagem .tar
Na máquina destino:
# docker load < /tmp/nome-nova-imagem .tar
# docker run <argumentos-para-container>
Verificar lista de camadas:
# docker history <nome-nova-imagem>
* Export e Import (congela todas a camadas)
# docker run -itd --name debiantest --net=container:test-mediawiki debian
https://forums.docker.com/t/shared-network-namespaces-using-net-container/16697/4
$ docker run -it --name myTomcat --net=myNetwork tomcat
$ docker run -it --net container:myTomcat busybox
#################################
#stack.yml
version:
'3.1'
services:
mongo:
image:
mongo
restart:
always
environment:
MONGO_INITDB_ROOT_USERNAME:
root
MONGO_INITDB_ROOT_PASSWORD:
example
mongo-express:
image:
mongo-express
restart:
always
ports:
-
8081:8081
environment:
ME_CONFIG_MONGODB_ADMINUSERNAME:
root
ME_CONFIG_MONGODB_ADMINPASSWORD:
example
#################################
$ docker stack deploy -c stack.yml mongo / $ docker-compose -f stack.yml up
Referência: https://hub.docker.com/_/mongo/
Multiplos container started
https://www.digitalocean.com/community/tutorials/how-to-install-and-use-docker-getting-started
https://docs.docker.com/samples/
Instalação do Docker no Debian / Ubuntu
# apt install systemd-docker docker.io
# systemctl start docker
# docker info
Imagem
# docker search centos
# docker pull centos
# docker images
Create minha imagem sem base source
https://docs.docker.com/engine/userguide/eng-image/baseimages/#create-a-full-image-using-tar
https://rominirani.com/docker-tutorial-series-writing-a-dockerfile-ce5746617cd
root@note:~/onlybash# ls
bin Dockerfile lib lib64
root@note:~/onlybash# cat Dockerfile
FROM scratch
ADD /bin /bin
ADD /lib /lib
ADD /lib64 /lib64
RUN /bin/bash
# docker build -t onlybash .
Executa o comando LS e quando termina ele finaliza o docker, mas arquivos continua, você consegue dar o docker start novamente no processo.
# docker run onlybash ls
** docker start 34de3d34d32
** docker start -i 34de3d34d32
root@note:/# docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
b8b705b7543d onlybash "ls" 9 seconds ago Exited (0) 7 seconds ago determined_euler
2c5c39f80933 onlybash "/bin/bash" 2 minutes ago Exited (0) 14 seconds ago evil_boyd
f20039ae5e10 onlybash "/bin/bash" 4 minutes ago Exited (0) 3 minutes ago dreamy_raman
root@note:/# docker start b8b705b7543d
b8b705b7543d
root@note:/# docker start -i b8b705b7543d
bin dev etc lib lib64 proc sys
Executa o comando bash e só termina quando é fechado o bash
# docker run -it onlybash /bin/bash
Processos que foram executados
# docker ps -a
Processos que estão em execução
# docker ps
https://www.digitalocean.com/community/tutorials/how-to-install-and-use-docker-getting-started
* Executa em um container existente um comando
# docker exec -it f20039ae5e10 /bin/bash
root@note:~# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
6516d128243e onlybash "/bin/bash" 6 seconds ago Up 5 seconds peaceful_davinci
root@note:~# docker exec -it 6516d128243e /bin/bash
bash-4.3#
Ferramentas de gerenciamento:
Cockpit
Magnum (cluster over VMs)
Zen ()
apt-get update apt-get -y install apt-transport-https ca-certificates curl software-properties-common curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add - apt-key fingerprint 0EBFCD88 add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable" apt-get update apt-get -y install docker-ce docker ps iptables -L -n sudo ufw allow 2376/tcp && sudo ufw allow 7946/udp && sudo ufw allow 7946/tcp && sudo ufw allow 80/tcp && sudo ufw allow 2377/tcp && sudo ufw allow 4789/udp sudo ufw reload && sudo ufw systemctl restart docker docker swarm init --advertise-addr 172.20.0.32 > /root/docker-swarm-join
install docker and after execute: docker swarm join --token xxxxxxxxxxxxtokenxxxxxxxxxxxxxxxxx 172.20.0.32:2377
# network stack
https://blog.alexellis.io/docker-stacks-attachable-networks/
# network standalone
https://docs.docker.com/network/network-tutorial-standalone/
https://medium.com/@hafandhalf/networking-between-docker-containers-1d718f22424
https://dev.to/mozartted/docker-networking--how-to-connect-multiple-containers-7fl
https://runnable.com/docker/docker-compose-networking
https://medium.com/@havloujian.joachim/advanced-docker-networking-outgoing-ip-921fc3090b09
# acessando netns
https://www.thegeekdiary.com/how-to-access-docker-containers-network-namespace-from-host/
# network arch
https://platform9.com/blog/container-namespaces-deep-dive-container-networking/
# diferença docker compose e docker stack
https://vsupalov.com/difference-docker-compose-and-docker-stack/
Install docker-ce centos https://syslint.com/blog/tutorial/install-docker-cecommunity-edition-in-centos-7/ Install docker-compose com pip https://github.com/NaturalHistoryMuseum/scratchpads2/wiki/Install-Docker-and-Docker-Compose-(Centos-7)
Rede default docker 0
estrategia 1 (compartilha pilha de rede do host)
docker run --network=host ... (localhost)
docker run --network=host ... (localhost)
estrategia 2 (compartilha pilha de rede container entre eles)
docker run --name nomeprimeirocontainer ... (localhost)
docker run --net=container:nomeprimeirocontainer (localhost)
estrategia 3 (cada um com sua pilha de rede, mas resolver nomecontainer para IP)
docker run --name nomecontainer1 ...
docker run --name nomecontainer2 --link nomecontainer1 ... (nomecontainer) --> IP
Banco de dados
Backend
Frontend
docker run --name containerbancodados ...
docker run --name backend --link containerbancodados ... (containerbancodados -> IP)
docker run --name frontend --link backend --link containerbancodados ... (containerbancodados -> IP) (backend -> IP)