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Version : 2021.01
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DOF202 - Docker Compose, Docker Machine et Docker Swarm
Contenu du Module
- DOF202 - Docker Compose, Docker Machine et Docker Swarm
- Contenu du Module
- LAB #1 - Docker Compose
- 1.1 - Installation
- 1.2 - Utiliser docker-compose
- LAB #2 - Docker Machine
- 2.1 - Présentation
- 2.2 - Création de Machines Virtuelles Docker
- 2.3 - Lister les VM Docker
- 2.4 - Obtenir l'adresse IP des VM
- 2.5 - Se connecter à une VM Docker
- LAB #3 - Docker Swarm
- 3.1 - Présentation
- 3.2 - Initialiser Docker Swarm
- 3.3 - Le Statut Leader
- 3.4 - Rejoindre le Swarm
- 3.5 - Consulter les Informations de Swarm
- 3.6 - Démarrer un Service
- 3.7 - Augmentation et Réduction du Service
- 3.8 - Consulter le Statut d'un Nœud
- 3.9 - Haute Disponibilité
- 3.10 - Supprimer un Service
LAB #1 - Docker Compose
Docker Compose est un utilitaire de compilation d'images et de gestion de conteneurs multiples, tous intégrés dans une seule et unique application logicielle. Son rôle est de rendre plus aisée la manipulation d'éléments multiples interconnectés. Pour ce faire, Docker Compose utilise un fichier dénommé docker-compose.yml au format YAML.
Ce fichier, appelé par la commande docker-compose build commence avec un mot clef image ou build selon que l'image est récupérée sur un registre ou provient du répertoire cité dans le fichier. Le reste du fichier contient des instructions pour définir la compilation des images constituantes, pour lier des conteneurs et pour définir l'environnement.
Une fois totalement construite, l'application peut ensuite être pilotée très simplement par l'utilisation de la commande docker-compose qui réagit de la même manière que la commande docker mais cette fois-ci sur tous les conteneurs définis dans le fichier docker-compose.yml.
De cette façon il est possible de démarrer l'application avec la commande docker-compose up, de l'arrêter avec la commande docker-compose stop ou de la redémarrer avec la commande docker-compose restart. De la même manière que la commande docker, la commande docker-compose donne accès aux journaux grâce à la commande docker-compose logs.
1.1 - Installation
Récupérez docker-compose avec curl :
root@debian9:~# curl -L "https://github.com/docker/compose/releases/download/1.23.2/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 617 0 617 0 0 912 0 --:--:-- --:--:-- --:--:-- 912
100 5140k 100 5140k 0 0 2145k 0 0:00:02 0:00:02 --:--:-- 5232k
root@debian9:~# chmod +x /usr/local/bin/docker-compose
Rendez /usr/local/bin/docker-compose exécutable :
root@debian9:~# ls -l /usr/local/bin/docker-compose -rw-r--r-- 1 root staff 5263681 Jan 2 16:29 /usr/local/bin/docker-compose root@debian9:~# chmod u+x /usr/local/bin/docker-compose
Avant de commencer, installez l'utilitaire tree :
root@debian9:~# apt-get install tree Reading package lists... Done Building dependency tree Reading state information... Done The following NEW packages will be installed: tree 0 upgraded, 1 newly installed, 0 to remove and 99 not upgraded. Need to get 45.9 kB of archives. After this operation, 102 kB of additional disk space will be used. Get:1 http://ftp.fr.debian.org/debian/ jessie/main tree amd64 1.7.0-3 [45.9 kB] Fetched 45.9 kB in 0s (429 kB/s) Selecting previously unselected package tree. (Reading database ... 100654 files and directories currently installed.) Preparing to unpack .../tree_1.7.0-3_amd64.deb ... Unpacking tree (1.7.0-3) ... Processing triggers for man-db (2.7.0.2-5) ... Setting up tree (1.7.0-3) ...
1.2 - Utiliser docker-compose
Une Application Simple
Dans ce LAB vous allez créer une application simple ayant deux environnements différents :
- development
- production
afin d'utiliser deux configurations différentes selon l'environnement désiré.
Commencez par créer l'arborescence du projet :
root@debian9:~# mkdir -p MyApp/common root@debian9:~# mkdir -p MyApp/development/content root@debian9:~# mkdir -p MyApp/production/content root@debian9:~# touch MyApp/common/docker-compose.yml MyApp/development/docker-compose.yml MyApp/production/docker-compose.yml root@debian9:~# touch MyApp/production/content/Dockerfile MyApp/production/content/index.html root@debian9:~# touch MyApp/development/content/Dockerfile MyApp/development/content/index.html
Utilisez l'utilitaire tree pour visualiser la structure du projet :
root@debian9:~# cd MyApp
root@debian9:~/MyApp# tree
.
├── common
│ └── docker-compose.yml
├── development
│ ├── content
│ │ ├── Dockerfile
│ │ └── index.html
│ └── docker-compose.yml
└── production
├── content
│ ├── Dockerfile
│ └── index.html
└── docker-compose.yml
5 directories, 7 files
Ce projet comporte la structure suivante :
- common
- La configuration commune aux deux environnements sera placée dans le fichier MyApp/common/docker-compose.yml.
- development
- La configuration spécifique à l'environnement development sera placée dans le fichier MyApp/development/docker-compose.yml. Le contenu du fichier index.html sera This is the development environement.
- production
- La configuration spécifique à l'environnement production sera placée dans le fichier MyApp/production/docker-compose.yml. Le contenu du fichier index.html sera This is the production environment.
Commencez par la création des deux Dockerfile pour development et production. Afin de garder l'exemple le plus simple que possible, ces deux fichiers sont identiques :
root@debian9:~/MyApp# vi development/content/Dockerfile root@debian9:~/MyApp# cat development/content/Dockerfile FROM tianon/true VOLUME ["/usr/share/nginx/html/"] ADD index.html /usr/share/nginx/html/ root@debian9:~/MyApp# cp development/content/Dockerfile production/content/Dockerfile
Créez maintenant le fichier MyApp/common/docker-compose.yml :
root@debian9:~/MyApp# vi common/docker-compose.yml
root@debian9:~/MyApp# cat common/docker-compose.yml
web:
image: nginx
ports:
- 8082:80
Les deux fichiers MyApp/development/docker-compose.yml et MyApp/production/docker-compose.yml sont identiques :
root@debian9:~/MyApp# vi development/docker-compose.yml
root@debian9:~/MyApp# cat development/docker-compose.yml
web:
extends:
file: ../common/docker-compose.yml
service: web
volumes_from:
- content
content:
build: content
root@debian9:~/MyApp# cp development/docker-compose.yml production/docker-compose.yml
Éditez maintenant les deux fichiers index.html :
root@debian9:~/MyApp# vi development/content/index.html root@debian9:~/MyApp# cat development/content/index.html <html> <body> <center>This is the development environement</center> </body> </html> root@debian9:~/MyApp# vi production/content/index.html root@debian9:~/MyApp# cat production/content/index.html <html> <body> <center>This is the production environement</center> </body> </html>
Placez-vous dans le sous-répertoire development et exécutez la commande docker-compose up -d :
root@debian9:~/MyApp/development# docker-compose up -d Creating development_content_1... Building content... Step 1/3 : FROM tianon/true ---> 1298b2036003 Step 2/3 : VOLUME /usr/share/nginx/html/ ---> Running in 8619de833add ---> 694e4f111996 Removing intermediate container 8619de833add Step 3/3 : ADD index.html /usr/share/nginx/html/ ---> f6fabac6703b Removing intermediate container a9bec35dba66 Successfully built f6fabac6703b Successfully tagged development_content:latest Creating development_web_1...
La commande docker-compose up est une abréviation des commandes docker-compose build && docker-compose run. L'option -d a le même effet de son homologue de la commande docker.
Les options de la commande docker-compose sont :
root@debian9:~# docker-compose --help Fast, isolated development environments using Docker. Usage: docker-compose [options] [COMMAND] [ARGS...] docker-compose -h|--help Options: --verbose Show more output --version Print version and exit -f, --file FILE Specify an alternate compose file (default: docker-compose.yml) -p, --project-name NAME Specify an alternate project name (default: directory name) Commands: build Build or rebuild services help Get help on a command kill Kill containers logs View output from containers port Print the public port for a port binding ps List containers pull Pulls service images rm Remove stopped containers run Run a one-off command scale Set number of containers for a service start Start services stop Stop services restart Restart services up Create and start containers
Vérifiez que l'image development_content a été créée :
root@debian9:~/MyApp/development# docker images REPOSITORY TAG IMAGE ID CREATED SIZE development_content latest f6fabac6703b 19 seconds ago 209B ...
Constatez la présence des deux conteneurs nginx:latest et development_content :
root@debian9:~/MyApp/development# docker ps -a CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 6955516dceff nginx:latest "nginx -g 'daemon ..." 28 seconds ago Up 27 seconds 0.0.0.0:8082->80/tcp development_web_1 9a1876d7a145 development_content "/true" 28 seconds ago Exited (0) 27 seconds ago development_content_1 ...
Utilisez maintenant lynx pour consultez http://localhost:8082 :
root@debian9:~/MyApp/development# lynx --dump http://localhost:8082
This is the development environement
root@debian9:~/MyApp/development#
Arrêtez docker-compose :
root@debian9:~/MyApp/development# docker-compose stop Stopping development_web_1... root@debian9:~/MyApp/development# docker ps -a CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 6955516dceff nginx:latest "nginx -g 'daemon ..." About a minute ago Exited (0) 5 seconds ago development_web_1 9a1876d7a145 development_content "/true" About a minute ago Exited (0) About a minute ago development_content_1 ...
Placez-vous maintenant dans le sous-répertoire production et exécutez de nouveau la commande docker-compose up -d :
root@debian9:~/MyApp/development# cd ../production/ root@debian9:~/MyApp/production# docker-compose up -d Creating production_content_1... Building content... Step 1/3 : FROM tianon/true ---> 1298b2036003 Step 2/3 : VOLUME /usr/share/nginx/html/ ---> Using cache ---> 694e4f111996 Step 3/3 : ADD index.html /usr/share/nginx/html/ ---> 61bcd73aff6e Removing intermediate container 18af8bcb48ce Successfully built 61bcd73aff6e Successfully tagged production_content:latest Creating production_web_1...
Notez la création du conteneur production_content :
root@debian9:~/MyApp/production# docker ps -a CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 8a2c7346a5db nginx:latest "nginx -g 'daemon ..." 4 seconds ago Up 3 seconds 0.0.0.0:8082->80/tcp production_web_1 5fde5e7cbd47 production_content "/true" 4 seconds ago Exited (0) 3 seconds ago production_content_1 6955516dceff nginx:latest "nginx -g 'daemon ..." 2 minutes ago Exited (0) About a minute ago development_web_1 9a1876d7a145 development_content "/true" 2 minutes ago Exited (0) 2 minutes ago development_content_1 ...
En étant dans le contexte production, il est possible d'utiliser la commande docker-compose ps :
root@debian9:~/MyApp/production# docker-compose ps
Name Command State Ports
---------------------------------------------------------------------------
production_content_1 /true Exit 0
production_web_1 nginx -g daemon off; Up 0.0.0.0:8082->80/tcp
De même en utilisant la même commande dans le répertoire development, on peut constater l'état de l'environnement development :
root@debian9:~/MyApp/production# cd ../development/
root@debian9:~/MyApp/development# docker-compose ps
Name Command State Ports
-------------------------------------------------------------
development_content_1 /true Exit 0
development_web_1 nginx -g daemon off; Exit 0
Utilisez maintenant lynx pour consultez http://localhost:8082 :
root@debian9:~/MyApp/development# lynx --dump http://localhost:8082
This is the production environement
root@debian9:~/MyApp/development#
Installer Wordpress avec Docker Compose
Créez maintenant le répertoire wordpress1 dans /root :
root@debian9:~/MyApp/development# cd ~ root@debian9:~# mkdir wordpress1
Placez-vous dans le répertoire et créer le fichier docker-compose.yaml
root@debian9:~# cd wordpress1
root@debian9:~/wordpress1# vi docker-compose.yaml
root@debian9:~/wordpress1# cat docker-compose.yaml
version: '3.3'
services:
db:
image: mysql:5.7
volumes:
- db_data:/var/lib/mysql
restart: always
environment:
MYSQL_ROOT_PASSWORD: fenestros
MYSQL_DATABASE: wordpress
MYSQL_USER: wordpress
MYSQL_PASSWORD: wordpress
wordpress:
depends_on:
- db
image: wordpress:latest
ports:
- "8000:80"
restart: always
environment:
WORDPRESS_DB_HOST: db:3306
WORDPRESS_DB_USER: wordpress
WORDPRESS_DB_PASSWORD: wordpress
WORDPRESS_DB_NAME: wordpress
volumes:
db_data: {}
Exécutez la commande docker-compose :
root@debian9:~/wordpress1# docker-compose up -d
Vérifiez que le Wordpress fonctionne :
root@debian9:~/wordpress# lynx --dump http://10.0.2.60:8000
[1]WordPress
Select a default language [English (United States)________]
Continue
References
1. https://wordpress.org/
root@debian9:~/wordpress# docker inspect wordpress | grep IPAddress
"SecondaryIPAddresses": null,
"IPAddress": "172.17.0.3",
"IPAddress": "172.17.0.3",
root@debian9:~/wordpress# lynx --dump http://172.17.0.3
[1]WordPress
Select a default language [English (United States)________]
Continue
References
1. https://wordpress.org/
LAB #2 - Docker Machine
2.1 - Présentation
Docker Machine est un outil qui vous permet d'installer docker sur des hôtes virtuels et de gérer les hôtes en utilisant des commandes spécifiques à docker-machine. Il est donc possible d'utiliser cet outil pour créer des hôtes docker localement, sur le réseau, dans un data center ou dans le cloud (Azure, AWS, Digital Ocean par exemple).
Le jeu de commandes de docker-machine permet de démarrer, surveiller, arrêter et re-démarrer un hôte géré, de mettre à jour le client/daemon docker et de configurer un client docker afin qu'il “parle” à votre machine hôte.
Pour installer docker-machine sur votre VM debian9, utilisez la commande suivante :
root@debian9:~# curl -L https://github.com/docker/machine/releases/download/v0.12.2/docker-machine-`uname -s`-`uname -m` >/tmp/docker-machine && chmod +x /tmp/docker-machine && cp /tmp/docker-machine /usr/local/bin/docker-machine
2.2 - Création de Machines Virtuelles Docker
La création d'une machine se fait simplement en utilisant la commande docker-machine avec la sous-commande create. Cette sous-commande prend l'option –driver ou -d qui indique le fournisseur à utiliser :
Commencez par installer Oracle VirtualBox:
root@debian9:~/wordpress# cd ~ root@debian9:~# apt install virtualbox-6.1
Créez maintenant la machine virtuelle manager1 :
root@debian9:~# docker-machine create --driver virtualbox manager1 Creating CA: /root/.docker/machine/certs/ca.pem Creating client certificate: /root/.docker/machine/certs/cert.pem Running pre-create checks... (manager1) Image cache directory does not exist, creating it at /root/.docker/machine/cache... (manager1) No default Boot2Docker ISO found locally, downloading the latest release... (manager1) Latest release for github.com/boot2docker/boot2docker is v17.06.2-ce (manager1) Downloading /root/.docker/machine/cache/boot2docker.iso from https://github.com/boot2docker/boot2docker/releases/download/v17.06.2-ce/boot2docker.iso... (manager1) 0%....10%....20%....30%....40%....50%....60%....70%....80%....90%....100% Creating machine... (manager1) Copying /root/.docker/machine/cache/boot2docker.iso to /root/.docker/machine/machines/manager1/boot2docker.iso... (manager1) Creating VirtualBox VM... (manager1) Creating SSH key... (manager1) Starting the VM... (manager1) Check network to re-create if needed... (manager1) Found a new host-only adapter: "vboxnet0" (manager1) Waiting for an IP... Waiting for machine to be running, this may take a few minutes... Detecting operating system of created instance... Waiting for SSH to be available... Detecting the provisioner... Provisioning with boot2docker... Copying certs to the local machine directory... Copying certs to the remote machine... Setting Docker configuration on the remote daemon... Checking connection to Docker... Docker is up and running! To see how to connect your Docker Client to the Docker Engine running on this virtual machine, run: docker-machine env manager1
Les options de la commande docker-machine sont :
root@debian9:~# docker-machine --help Usage: docker-machine [OPTIONS] COMMAND [arg...] Create and manage machines running Docker. Version: 0.12.2, build 9371605 Author: Docker Machine Contributors - <https://github.com/docker/machine> Options: --debug, -D Enable debug mode --storage-path, -s "/root/.docker/machine" Configures storage path [$MACHINE_STORAGE_PATH] --tls-ca-cert CA to verify remotes against [$MACHINE_TLS_CA_CERT] --tls-ca-key Private key to generate certificates [$MACHINE_TLS_CA_KEY] --tls-client-cert Client cert to use for TLS [$MACHINE_TLS_CLIENT_CERT] --tls-client-key Private key used in client TLS auth [$MACHINE_TLS_CLIENT_KEY] --github-api-token Token to use for requests to the Github API [$MACHINE_GITHUB_API_TOKEN] --native-ssh Use the native (Go-based) SSH implementation. [$MACHINE_NATIVE_SSH] --bugsnag-api-token BugSnag API token for crash reporting [$MACHINE_BUGSNAG_API_TOKEN] --help, -h show help --version, -v print the version Commands: active Print which machine is active config Print the connection config for machine create Create a machine env Display the commands to set up the environment for the Docker client inspect Inspect information about a machine ip Get the IP address of a machine kill Kill a machine ls List machines provision Re-provision existing machines regenerate-certs Regenerate TLS Certificates for a machine restart Restart a machine rm Remove a machine ssh Log into or run a command on a machine with SSH. scp Copy files between machines start Start a machine status Get the status of a machine stop Stop a machine upgrade Upgrade a machine to the latest version of Docker url Get the URL of a machine version Show the Docker Machine version or a machine docker version help Shows a list of commands or help for one command Run 'docker-machine COMMAND --help' for more information on a command.
Créez maintenant 5 travailleurs - worker1 jusqu'à worker5 :
root@debian9:~# docker-machine create --driver virtualbox worker1 Running pre-create checks... Creating machine... (worker1) Copying /root/.docker/machine/cache/boot2docker.iso to /root/.docker/machine/machines/worker1/boot2docker.iso... (worker1) Creating VirtualBox VM... (worker1) Creating SSH key... (worker1) Starting the VM... (worker1) Check network to re-create if needed... (worker1) Waiting for an IP... Waiting for machine to be running, this may take a few minutes... Detecting operating system of created instance... Waiting for SSH to be available... Detecting the provisioner... Provisioning with boot2docker... Copying certs to the local machine directory... Copying certs to the remote machine... Setting Docker configuration on the remote daemon... Checking connection to Docker... Docker is up and running! To see how to connect your Docker Client to the Docker Engine running on this virtual machine, run: docker-machine env worker1
root@debian9:~# docker-machine create --driver virtualbox worker2 ... root@debian9:~# docker-machine create --driver virtualbox worker3 ... root@debian9:~# docker-machine create --driver virtualbox worker4 ... root@debian9:~# docker-machine create --driver virtualbox worker5 ...
Les options de la sous-commande create de la commande docker-machine sont :
root@debian9:~# docker-machine create --help Usage: docker-machine create [OPTIONS] [arg...] Create a machine Description: Run 'docker-machine create --driver name' to include the create flags for that driver in the help text. Options: --driver, -d "virtualbox" Driver to create machine with. [$MACHINE_DRIVER] --engine-env [--engine-env option --engine-env option] Specify environment variables to set in the engine --engine-insecure-registry [--engine-insecure-registry option --engine-insecure-registry option] Specify insecure registries to allow with the created engine --engine-install-url "https://get.docker.com" Custom URL to use for engine installation [$MACHINE_DOCKER_INSTALL_URL] --engine-label [--engine-label option --engine-label option] Specify labels for the created engine --engine-opt [--engine-opt option --engine-opt option] Specify arbitrary flags to include with the created engine in the form flag=value --engine-registry-mirror [--engine-registry-mirror option --engine-registry-mirror option] Specify registry mirrors to use [$ENGINE_REGISTRY_MIRROR] --engine-storage-driver Specify a storage driver to use with the engine --swarm Configure Machine to join a Swarm cluster --swarm-addr addr to advertise for Swarm (default: detect and use the machine IP) --swarm-discovery Discovery service to use with Swarm --swarm-experimental Enable Swarm experimental features --swarm-host "tcp://0.0.0.0:3376" ip/socket to listen on for Swarm master --swarm-image "swarm:latest" Specify Docker image to use for Swarm [$MACHINE_SWARM_IMAGE] --swarm-join-opt [--swarm-join-opt option --swarm-join-opt option] Define arbitrary flags for Swarm join --swarm-master Configure Machine to be a Swarm master --swarm-opt [--swarm-opt option --swarm-opt option] Define arbitrary flags for Swarm master --swarm-strategy "spread" Define a default scheduling strategy for Swarm --tls-san [--tls-san option --tls-san option] Support extra SANs for TLS certs --virtualbox-boot2docker-url The URL of the boot2docker image. Defaults to the latest available version [$VIRTUALBOX_BOOT2DOCKER_URL] --virtualbox-cpu-count "1" number of CPUs for the machine (-1 to use the number of CPUs available) [$VIRTUALBOX_CPU_COUNT] --virtualbox-disk-size "20000" Size of disk for host in MB [$VIRTUALBOX_DISK_SIZE] --virtualbox-host-dns-resolver Use the host DNS resolver [$VIRTUALBOX_HOST_DNS_RESOLVER] --virtualbox-hostonly-cidr "192.168.99.1/24" Specify the Host Only CIDR [$VIRTUALBOX_HOSTONLY_CIDR] --virtualbox-hostonly-nicpromisc "deny" Specify the Host Only Network Adapter Promiscuous Mode [$VIRTUALBOX_HOSTONLY_NIC_PROMISC] --virtualbox-hostonly-nictype "82540EM" Specify the Host Only Network Adapter Type [$VIRTUALBOX_HOSTONLY_NIC_TYPE] --virtualbox-hostonly-no-dhcp Disable the Host Only DHCP Server [$VIRTUALBOX_HOSTONLY_NO_DHCP] --virtualbox-import-boot2docker-vm The name of a Boot2Docker VM to import [$VIRTUALBOX_BOOT2DOCKER_IMPORT_VM] --virtualbox-memory "1024" Size of memory for host in MB [$VIRTUALBOX_MEMORY_SIZE] --virtualbox-nat-nictype "82540EM" Specify the Network Adapter Type [$VIRTUALBOX_NAT_NICTYPE] --virtualbox-no-dns-proxy Disable proxying all DNS requests to the host [$VIRTUALBOX_NO_DNS_PROXY] --virtualbox-no-share Disable the mount of your home directory [$VIRTUALBOX_NO_SHARE] --virtualbox-no-vtx-check Disable checking for the availability of hardware virtualization before the vm is started [$VIRTUALBOX_NO_VTX_CHECK] --virtualbox-share-folder Mount the specified directory instead of the default home location. Format: dir:name [$VIRTUALBOX_SHARE_FOLDER] --virtualbox-ui-type "headless" Specify the UI Type: (gui|sdl|headless|separate) [$VIRTUALBOX_UI_TYPE]
2.3 - Lister les VM Docker
Pour lister les VM Docker ainsi que leurs états, il convient d'utilise la sous-commande ls de la commande docker-machine :
root@debian9:~# docker-machine ls NAME ACTIVE DRIVER STATE URL SWARM DOCKER ERRORS manager1 - virtualbox Running tcp://192.168.99.100:2376 v17.06.2-ce worker1 - virtualbox Running tcp://192.168.99.101:2376 v17.06.2-ce worker2 - virtualbox Running tcp://192.168.99.102:2376 v17.06.2-ce worker3 - virtualbox Running tcp://192.168.99.103:2376 v17.06.2-ce worker4 - virtualbox Running tcp://192.168.99.104:2376 v17.06.2-ce worker5 - virtualbox Running tcp://192.168.99.105:2376 v17.06.2-ce
2.4 - Obtenir l'adresse IP des VM
Une autre façon d'obtenir les adresses IP des VM est d'utiliser la sous-commande ip :
root@debian9:~# docker-machine ip manager1 192.168.99.100 root@debian9:~# docker-machine ip worker1 192.168.99.101 root@debian9:~# docker-machine ip worker2 192.168.99.102 root@debian9:~# docker-machine ip worker3 192.168.99.103 root@debian9:~# docker-machine ip worker4 192.168.99.104 root@debian9:~# docker-machine ip worker5 192.168.99.105
2.5 - Se connecter à une VM Docker
Pour se connecter à une VM Docker, il convient d'utiliser la sous-commande ssh de la commande docker-machine :
root@debian9:~# docker-machine ssh manager1
## .
## ## ## ==
## ## ## ## ## ===
/"""""""""""""""""\___/ ===
~~~ {~~ ~~~~ ~~~ ~~~~ ~~~ ~ / ===- ~~~
\______ o __/
\ \ __/
\____\_______/
_ _ ____ _ _
| |__ ___ ___ | |_|___ \ __| | ___ ___| | _____ _ __
| '_ \ / _ \ / _ \| __| __) / _` |/ _ \ / __| |/ / _ \ '__|
| |_) | (_) | (_) | |_ / __/ (_| | (_) | (__| < __/ |
|_.__/ \___/ \___/ \__|_____\__,_|\___/ \___|_|\_\___|_|
Boot2Docker version 17.06.2-ce, build HEAD : ff16afa - Wed Sep 6 00:17:25 UTC 2017
Docker version 17.06.2-ce, build cec0b72
docker@manager1:~$ exit
Important - Notez que la distribution de la VM est Boot2Docker. Cette distribution est basée sur Tiny Core Linux, s'exécute entièrement dans la mémoire vive, pèse 27 Mo et démarre en approximativement 5 secondes.
Installez maintenant le paquet mlocate :
root@debian9:~# apt install mlocate ...
Ayant été créées par root, les VM Docker ainsi que leurs fichiers associés sont stockés dans le répertoire /root/.docker/machine/machines/ :
root@debian9:~# updatedb root@debian9:~# locate manager1 /root/.docker/machine/machines/manager1 /root/.docker/machine/machines/manager1/boot2docker.iso /root/.docker/machine/machines/manager1/ca.pem /root/.docker/machine/machines/manager1/cert.pem /root/.docker/machine/machines/manager1/config.json /root/.docker/machine/machines/manager1/disk.vmdk /root/.docker/machine/machines/manager1/id_rsa /root/.docker/machine/machines/manager1/id_rsa.pub /root/.docker/machine/machines/manager1/key.pem /root/.docker/machine/machines/manager1/manager1 /root/.docker/machine/machines/manager1/server-key.pem /root/.docker/machine/machines/manager1/server.pem /root/.docker/machine/machines/manager1/manager1/Logs /root/.docker/machine/machines/manager1/manager1/manager1.vbox /root/.docker/machine/machines/manager1/manager1/manager1.vbox-prev /root/.docker/machine/machines/manager1/manager1/Logs/VBox.log
LAB #3 - Docker Swarm
3.1 - Présentation
Docker Swarm est un utilitaire qui permet de gérer un cluster pour déployer des conteneurs en permettant une imitation du comportement de docker sur une seule machine.
3.2 - Initialiser Docker Swarm
Pour initialiser Docker swarm, il convient d'utiliser la commande docker swarm init à partir de la VM Docker manager1 en stipulant l'adresse IP de manager1 :
root@debian9:~# docker-machine ssh manager1
docker@manager1:~$ docker swarm init --advertise-addr 192.168.99.100
Swarm initialized: current node (yuwpmvtfmdxn8i7nllkyzkxkp) is now a manager.
To add a worker to this swarm, run the following command:
docker swarm join --token SWMTKN-1-5bd9w9tapfqmd41f2psqdkoqwfo48fqsznnalk2slc28vlp6uh-004kp8y71m09nd7p8ft7ldku0 192.168.99.100:2377
To add a manager to this swarm, run 'docker swarm join-token manager' and follow the instructions.
Notez que les ports suivants doivent être ouverts sur un nœud manager : 22/tcp, 2376/tcp, 2377/tcp, 7946/tcp, 7946/udp et 4789/udp.
3.3 - Le Statut Leader
Consultez le statut de la VM Docker manager1 :
docker@manager1:~$ docker node ls ID HOSTNAME STATUS AVAILABILITY MANAGER STATUS yuwpmvtfmdxn8i7nllkyzkxkp * manager1 Ready Active Leader
A un instant t il ne peut y avoir q'un seul Leader. Il est possible de créer d'autres nœuds de gestion en le rejoignant à swarm en utilisant le token prévu à cet effet. Par contre ces nœuds de gestion restent en attente d'une éventuelle défaillance du Leader actuel.
Pour connaître le token nécessaire pour rejoindre swarm en tant que nœud de gestion, saisissez la commande suivante :
docker@manager1:~$ docker swarm join-token manager
To add a manager to this swarm, run the following command:
docker swarm join --token SWMTKN-1-5bd9w9tapfqmd41f2psqdkoqwfo48fqsznnalk2slc28vlp6uh-8rvbxvqewsrv6yyts7z2lq9pt 192.168.99.100:2377
3.4 - Rejoindre le Swarm
Rejoignez les 5 machines travailleurs à swarm en utilisant le token worker :
docker@worker1:~$ docker swarm join --token SWMTKN-1-5bd9w9tapfqmd41f2psqdkoqwfo48fqsznnalk2slc28vlp6uh-004kp8y71m09nd7p8ft7ldku0 192.168.99.100:2377 This node joined a swarm as a worker.
docker@worker2:~$ docker swarm join --token SWMTKN-1-5bd9w9tapfqmd41f2psqdkoqwfo48fqsznnalk2slc28vlp6uh-004kp8y71m09nd7p8ft7ldku0 192.168.99.100:2377 This node joined a swarm as a worker.
docker@worker3:~$ docker swarm join --token SWMTKN-1-5bd9w9tapfqmd41f2psqdkoqwfo48fqsznnalk2slc28vlp6uh-004kp8y71m09nd7p8ft7ldku0 192.168.99.100:2377 This node joined a swarm as a worker.
docker@worker4:~$ docker swarm join --token SWMTKN-1-5bd9w9tapfqmd41f2psqdkoqwfo48fqsznnalk2slc28vlp6uh-004kp8y71m09nd7p8ft7ldku0 192.168.99.100:2377 This node joined a swarm as a worker.
docker@worker5:~$ docker swarm join --token SWMTKN-1-5bd9w9tapfqmd41f2psqdkoqwfo48fqsznnalk2slc28vlp6uh-004kp8y71m09nd7p8ft7ldku0 192.168.99.100:2377 This node joined a swarm as a worker.
Notez que les ports suivants doivent être ouverts sur un nœud worker : 22/tcp, 2376/tcp, 7946/tcp, 7946/udp et 4789/udp.
L'état des VM Docker peut être consulter en utilisant de nouveau la commande docker node ls :
docker@manager1:~$ docker node ls ID HOSTNAME STATUS AVAILABILITY MANAGER STATUS 1f5qtolgtonqmhjk5ppwc8x1b worker1 Ready Active kmyjdwp9ojhzje4hlw7ffhuxv worker2 Ready Active oyszb44k8yw5btz3c1wq2ot2e worker4 Ready Active p6jpyopzzy0zg4znegi63hzjq worker5 Ready Active yitkfnk99ecisrny9g3r9kfhk worker3 Ready Active yuwpmvtfmdxn8i7nllkyzkxkp * manager1 Ready Active Leader
Notez que vous ne pouvez pas utiliser cette commande à partir d'un travailleur :
docker@worker5:~$ docker node ls Error response from daemon: This node is not a swarm manager. Worker nodes can't be used to view or modify cluster state. Please run this command on a manager node or promote the current node to a manager.
3.5 - Consulter les Informations de Swarm
Il est possible de visualiser les informations concernant le swarm en utilisant la commande docker info :
docker@manager1:~$ docker info ... Swarm: active NodeID: yuwpmvtfmdxn8i7nllkyzkxkp Is Manager: true ClusterID: sqll9xmii9qkrd35d1limn1od Managers: 1 Nodes: 6 Orchestration: Task History Retention Limit: 5 Raft: Snapshot Interval: 10000 Number of Old Snapshots to Retain: 0 Heartbeat Tick: 1 Election Tick: 3 Dispatcher: Heartbeat Period: 5 seconds CA Configuration: Expiry Duration: 3 months Force Rotate: 0 Root Rotation In Progress: false Node Address: 192.168.99.100 Manager Addresses: 192.168.99.100:2377 ...
Important - Quand le moteur Docker est en mode swarm, les noeuds de gestion implémentent le Raft Consensus Algorithm pour gérer l'état du cluster.
3.6 - Démarrer un Service
Dans cet exemple, nous allons démarrer le service nginx avec les propriétés suivantes :
- Mappage du port nginx sur le port 80 de la machine hôte,
- 5 instances du service,
- Un nom unique de web.
docker@manager1:~$ docker service create --replicas 5 -p 80:80 --name web nginx 4xtuwgbvr17lvfzoumh1y4mq4 Since --detach=false was not specified, tasks will be created in the background. In a future release, --detach=false will become the default.
Pour consulter l'état de ce service, utilisez la commande docker service ls :
docker@manager1:~$ docker service ls ID NAME MODE REPLICAS IMAGE PORTS 4xtuwgbvr17l web replicated 5/5 nginx:latest *:80->80/tcp
Ce service fonctionne dans des conteneurs Docker :
docker@manager1:~$ docker service ps web ID NAME IMAGE NODE DESIRED STATE CURRENT STATE ERROR PORTS jkm2hapcthht web.1 nginx:latest worker3 Running Running about a minute ago q55eqdhr1qf1 web.2 nginx:latest worker4 Running Running about a minute ago imqdkw4ei6gs web.3 nginx:latest manager1 Running Running about a minute ago k4vjd0g7ijww web.4 nginx:latest worker1 Running Running about a minute ago b7xbmy1npgf9 web.5 nginx:latest worker2 Running Running about a minute ago
Important - Notez qu'il n'y a pas de conteneur sur worker5.
Pour constater le lancement du daemon nginx, lancez la commande docker ps sur la machine manager1 :
docker@manager1:~$ docker ps CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 4107cb687eda nginx:latest "nginx -g 'daemon ..." 2 minutes ago Up 2 minutes 80/tcp web.3.imqdkw4ei6gskwacnb4pime5f
Connectez-vous sur chaque VM Docker pour constater que le service nginx fonctionne :
docker@manager1:/$ curl 192.168.99.100
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
body {
width: 35em;
margin: 0 auto;
font-family: Tahoma, Verdana, Arial, sans-serif;
}
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>
<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>
<p><em>Thank you for using nginx.</em></p>
</body>
</html>
docker@manager1:/$ curl 192.168.99.101
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
body {
width: 35em;
margin: 0 auto;
font-family: Tahoma, Verdana, Arial, sans-serif;
}
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>
<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>
<p><em>Thank you for using nginx.</em></p>
</body>
</html>
docker@manager1:/$ curl 192.168.99.102
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
body {
width: 35em;
margin: 0 auto;
font-family: Tahoma, Verdana, Arial, sans-serif;
}
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>
<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>
<p><em>Thank you for using nginx.</em></p>
</body>
</html>
docker@manager1:/$ curl 192.168.99.103
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
body {
width: 35em;
margin: 0 auto;
font-family: Tahoma, Verdana, Arial, sans-serif;
}
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>
<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>
<p><em>Thank you for using nginx.</em></p>
</body>
</html>
docker@manager1:/$ curl 192.168.99.104
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
body {
width: 35em;
margin: 0 auto;
font-family: Tahoma, Verdana, Arial, sans-serif;
}
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>
<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>
<p><em>Thank you for using nginx.</em></p>
</body>
</html>
docker@manager1:/$ curl 192.168.99.105
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
body {
width: 35em;
margin: 0 auto;
font-family: Tahoma, Verdana, Arial, sans-serif;
}
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>
<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>
<p><em>Thank you for using nginx.</em></p>
</body>
</html>
Important - Notez que le service est même disponible en consultant l'adresse IP de worker5.
3.7 - Augmentation et Réduction du Service
Actuellement, il existe 5 conteneurs en cours d'exécution. Pour procéder à un scale-up à 8 conteneurs, il convient d'utiliser la commande docker service scale :
docker@manager1:/$ docker service scale web=8 web scaled to 8
Notez que la commande docker service ls confirme le fait qu'il y a 8 replicas :
docker@manager1:/$ docker service ls ID NAME MODE REPLICAS IMAGE PORTS 4xtuwgbvr17l web replicated 8/8 nginx:latest *:80->80/tcp
Des trois replicas supplémentaires, deux ont été lancés sur worker5 tandis que le troisième a été lancé sur worker1 :
docker@manager1:/$ docker service ps web ID NAME IMAGE NODE DESIRED STATE CURRENT STATE ERROR PORTS jkm2hapcthht web.1 nginx:latest worker3 Running Running 20 minutes ago q55eqdhr1qf1 web.2 nginx:latest worker4 Running Running 20 minutes ago imqdkw4ei6gs web.3 nginx:latest manager1 Running Running 20 minutes ago k4vjd0g7ijww web.4 nginx:latest worker1 Running Running 20 minutes ago b7xbmy1npgf9 web.5 nginx:latest worker2 Running Running 20 minutes ago kg3bivcg0wln web.6 nginx:latest worker5 Running Running 47 seconds ago ik3u0jfgey64 web.7 nginx:latest worker5 Running Running 47 seconds ago 6bw5ptw7xao8 web.8 nginx:latest worker1 Running Running 57 seconds ago
3.8 - Consulter le Statut d'un Noeud
Pour se renseigner sur le statut du nœud courant, il convient d'utiliser la commande docker node inspect avec le mot clef self :
docker@manager1:/$ docker node inspect self
[
{
"ID": "yuwpmvtfmdxn8i7nllkyzkxkp",
"Version": {
"Index": 9
},
"CreatedAt": "2017-09-08T11:43:55.289178512Z",
"UpdatedAt": "2017-09-08T11:43:55.89870884Z",
"Spec": {
"Labels": {},
"Role": "manager",
"Availability": "active"
},
"Description": {
"Hostname": "manager1",
"Platform": {
"Architecture": "x86_64",
"OS": "linux"
},
"Resources": {
"NanoCPUs": 1000000000,
"MemoryBytes": 1044123648
},
"Engine": {
"EngineVersion": "17.06.2-ce",
"Labels": {
"provider": "virtualbox"
},
"Plugins": [
{
"Type": "Log",
"Name": "awslogs"
},
{
"Type": "Log",
"Name": "fluentd"
},
{
"Type": "Log",
"Name": "gcplogs"
},
{
"Type": "Log",
"Name": "gelf"
},
{
"Type": "Log",
"Name": "journald"
},
{
"Type": "Log",
"Name": "json-file"
},
{
"Type": "Log",
"Name": "logentries"
},
{
"Type": "Log",
"Name": "splunk"
},
{
"Type": "Log",
"Name": "syslog"
},
{
"Type": "Network",
"Name": "bridge"
},
{
"Type": "Network",
"Name": "host"
},
{
"Type": "Network",
"Name": "macvlan"
},
{
"Type": "Network",
"Name": "null"
},
{
"Type": "Network",
"Name": "overlay"
},
{
"Type": "Volume",
"Name": "local"
}
]
},
"TLSInfo": {
"TrustRoot": "-----BEGIN CERTIFICATE-----\nMIIBajCCARCgAwIBAgIUNuU4I89kxId2QXulofRKxJa9XRcwCgYIKoZIzj0EAwIw\nEzERMA8GA1UEAxMIc3dhcm0tY2EwHhcNMTcwOTA4MTEzOTAwWhcNMzcwOTAzMTEz\nOTAwWjATMREwDwYDVQQDEwhzd2FybS1jYTBZMBMGByqGSM49AgEGCCqGSM49AwEH\nA0IABEqgLUbyjyNuP35aAzW+aqVB8AkghvpF5hq1KnMveHbl4Ilr+EyDjlYZkbnt\nGb/xmsy/tOP8uz598ZX/JlR4fZyjQjBAMA4GA1UdDwEB/wQEAwIBBjAPBgNVHRMB\nAf8EBTADAQH/MB0GA1UdDgQWBBSzoKGrN0ELfEIMsjxuYj5LAckD2jAKBggqhkjO\nPQQDAgNIADBFAiB34DOvDtIYjJ+GzbPMGu9Dd/cJGvy7CJg1tNUG3SoOrAIhAJZ4\nTJBucTomFSDsj5Y/R6TfhcpXpsksk7JwYgEglu44\n-----END CERTIFICATE-----\n",
"CertIssuerSubject": "MBMxETAPBgNVBAMTCHN3YXJtLWNh",
"CertIssuerPublicKey": "MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAESqAtRvKPI24/floDNb5qpUHwCSCG+kXmGrUqcy94duXgiWv4TIOOVhmRue0Zv/GazL+04/y7Pn3xlf8mVHh9nA=="
}
},
"Status": {
"State": "ready",
"Addr": "192.168.99.100"
},
"ManagerStatus": {
"Leader": true,
"Reachability": "reachable",
"Addr": "192.168.99.100:2377"
}
}
]
Pour se renseigner sur le statut d'un autre nœud, il convient d'utiliser la commande docker node inspect avec le nom du nœud concerné :
docker@manager1:/$ docker node inspect worker1
[
{
"ID": "1f5qtolgtonqmhjk5ppwc8x1b",
"Version": {
"Index": 15
},
"CreatedAt": "2017-09-08T11:48:42.011596185Z",
"UpdatedAt": "2017-09-08T11:48:42.093455479Z",
"Spec": {
"Labels": {},
"Role": "worker",
"Availability": "active"
},
"Description": {
"Hostname": "worker1",
"Platform": {
"Architecture": "x86_64",
"OS": "linux"
},
"Resources": {
"NanoCPUs": 1000000000,
"MemoryBytes": 1044123648
},
"Engine": {
"EngineVersion": "17.06.2-ce",
"Labels": {
"provider": "virtualbox"
},
"Plugins": [
{
"Type": "Log",
"Name": "awslogs"
},
{
"Type": "Log",
"Name": "fluentd"
},
{
"Type": "Log",
"Name": "gcplogs"
},
{
"Type": "Log",
"Name": "gelf"
},
{
"Type": "Log",
"Name": "journald"
},
{
"Type": "Log",
"Name": "json-file"
},
{
"Type": "Log",
"Name": "logentries"
},
{
"Type": "Log",
"Name": "splunk"
},
{
"Type": "Log",
"Name": "syslog"
},
{
"Type": "Network",
"Name": "bridge"
},
{
"Type": "Network",
"Name": "host"
},
{
"Type": "Network",
"Name": "macvlan"
},
{
"Type": "Network",
"Name": "null"
},
{
"Type": "Network",
"Name": "overlay"
},
{
"Type": "Volume",
"Name": "local"
}
]
},
"TLSInfo": {
"TrustRoot": "-----BEGIN CERTIFICATE-----\nMIIBajCCARCgAwIBAgIUNuU4I89kxId2QXulofRKxJa9XRcwCgYIKoZIzj0EAwIw\nEzERMA8GA1UEAxMIc3dhcm0tY2EwHhcNMTcwOTA4MTEzOTAwWhcNMzcwOTAzMTEz\nOTAwWjATMREwDwYDVQQDEwhzd2FybS1jYTBZMBMGByqGSM49AgEGCCqGSM49AwEH\nA0IABEqgLUbyjyNuP35aAzW+aqVB8AkghvpF5hq1KnMveHbl4Ilr+EyDjlYZkbnt\nGb/xmsy/tOP8uz598ZX/JlR4fZyjQjBAMA4GA1UdDwEB/wQEAwIBBjAPBgNVHRMB\nAf8EBTADAQH/MB0GA1UdDgQWBBSzoKGrN0ELfEIMsjxuYj5LAckD2jAKBggqhkjO\nPQQDAgNIADBFAiB34DOvDtIYjJ+GzbPMGu9Dd/cJGvy7CJg1tNUG3SoOrAIhAJZ4\nTJBucTomFSDsj5Y/R6TfhcpXpsksk7JwYgEglu44\n-----END CERTIFICATE-----\n",
"CertIssuerSubject": "MBMxETAPBgNVBAMTCHN3YXJtLWNh",
"CertIssuerPublicKey": "MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAESqAtRvKPI24/floDNb5qpUHwCSCG+kXmGrUqcy94duXgiWv4TIOOVhmRue0Zv/GazL+04/y7Pn3xlf8mVHh9nA=="
}
},
"Status": {
"State": "ready",
"Addr": "192.168.99.101"
}
}
]
L'option –pretty produit une sortie plus facilement lisible :
docker@manager1:/$ docker node inspect --pretty worker1 ID: 1f5qtolgtonqmhjk5ppwc8x1b Hostname: worker1 Joined at: 2017-09-08 11:48:42.011596185 +0000 utc Status: State: Ready Availability: Active Address: 192.168.99.101 Platform: Operating System: linux Architecture: x86_64 Resources: CPUs: 1 Memory: 995.8MiB Plugins: Log: awslogs, fluentd, gcplogs, gelf, journald, json-file, logentries, splunk, syslog Network: bridge, host, macvlan, null, overlay Volume: local Engine Version: 17.06.2-ce Engine Labels: - provider=virtualbox TLS Info: TrustRoot: -----BEGIN CERTIFICATE----- MIIBajCCARCgAwIBAgIUNuU4I89kxId2QXulofRKxJa9XRcwCgYIKoZIzj0EAwIw EzERMA8GA1UEAxMIc3dhcm0tY2EwHhcNMTcwOTA4MTEzOTAwWhcNMzcwOTAzMTEz OTAwWjATMREwDwYDVQQDEwhzd2FybS1jYTBZMBMGByqGSM49AgEGCCqGSM49AwEH A0IABEqgLUbyjyNuP35aAzW+aqVB8AkghvpF5hq1KnMveHbl4Ilr+EyDjlYZkbnt Gb/xmsy/tOP8uz598ZX/JlR4fZyjQjBAMA4GA1UdDwEB/wQEAwIBBjAPBgNVHRMB Af8EBTADAQH/MB0GA1UdDgQWBBSzoKGrN0ELfEIMsjxuYj5LAckD2jAKBggqhkjO PQQDAgNIADBFAiB34DOvDtIYjJ+GzbPMGu9Dd/cJGvy7CJg1tNUG3SoOrAIhAJZ4 TJBucTomFSDsj5Y/R6TfhcpXpsksk7JwYgEglu44 -----END CERTIFICATE----- Issuer Subject: MBMxETAPBgNVBAMTCHN3YXJtLWNh Issuer Public Key: MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAESqAtRvKPI24/floDNb5qpUHwCSCG+kXmGrUqcy94duXgiWv4TIOOVhmRue0Zv/GazL+04/y7Pn3xlf8mVHh9nA==
3.9 - Haute Disponibilité
Quand un nœud est actif, il est capable de recevoir de nouvelles tâches à partir du manager :
- pendant un scale-up,
- pendant une une mise à jour progressive,
- quand un autre nœud reçois une instruction de se mettre en indisponibilité,
- quand un service se mets en échec sur un autre nœud
Rappelez-vous que la swarm contient 6 VM Docker :
docker@manager1:/$ docker node ls ID HOSTNAME STATUS AVAILABILITY MANAGER STATUS 1f5qtolgtonqmhjk5ppwc8x1b worker1 Ready Active kmyjdwp9ojhzje4hlw7ffhuxv worker2 Ready Active oyszb44k8yw5btz3c1wq2ot2e worker4 Ready Active p6jpyopzzy0zg4znegi63hzjq worker5 Ready Active yitkfnk99ecisrny9g3r9kfhk worker3 Ready Active yuwpmvtfmdxn8i7nllkyzkxkp * manager1 Ready Active Leader
et que sur les 6 VM Docker, il y a 8 conteneurs,
docker@manager1:/$ docker service ps web ID NAME IMAGE NODE DESIRED STATE CURRENT STATE ERROR PORTS jkm2hapcthht web.1 nginx:latest worker3 Running Running 25 minutes ago q55eqdhr1qf1 web.2 nginx:latest worker4 Running Running 25 minutes ago imqdkw4ei6gs web.3 nginx:latest manager1 Running Running 25 minutes ago k4vjd0g7ijww web.4 nginx:latest worker1 Running Running 25 minutes ago b7xbmy1npgf9 web.5 nginx:latest worker2 Running Running 25 minutes ago kg3bivcg0wln web.6 nginx:latest worker5 Running Running 5 minutes ago ik3u0jfgey64 web.7 nginx:latest worker5 Running Running 5 minutes ago 6bw5ptw7xao8 web.8 nginx:latest worker1 Running Running 5 minutes ago
dont deux se trouvent sur worker1 :
docker@manager1:/$ docker node ps worker1 ID NAME IMAGE NODE DESIRED STATE CURRENT STATE ERROR PORTS k4vjd0g7ijww web.4 nginx:latest worker1 Running Running 26 minutes ago 6bw5ptw7xao8 web.8 nginx:latest worker1 Running Running 6 minutes ago
Mettez worker1 en mode d'indisponibilité en utilisant l'option –availability drain :
docker@manager1:/$ docker node update --availability drain worker1 worker1
Constatez que le service web a été déplacé sur deux autres noeuds, manager1 et worker4 :
docker@manager1:/$ docker service ps web ID NAME IMAGE NODE DESIRED STATE CURRENT STATE ERROR PORTS jkm2hapcthht web.1 nginx:latest worker3 Running Running 29 minutes ago q55eqdhr1qf1 web.2 nginx:latest worker4 Running Running 29 minutes ago imqdkw4ei6gs web.3 nginx:latest manager1 Running Running 29 minutes ago 6cv6j4tz0nk5 web.4 nginx:latest manager1 Running Running 33 seconds ago k4vjd0g7ijww \_ web.4 nginx:latest worker1 Shutdown Shutdown 33 seconds ago b7xbmy1npgf9 web.5 nginx:latest worker2 Running Running 29 minutes ago kg3bivcg0wln web.6 nginx:latest worker5 Running Running 9 minutes ago ik3u0jfgey64 web.7 nginx:latest worker5 Running Running 9 minutes ago wht3r8c9wga6 web.8 nginx:latest worker4 Running Running 33 seconds ago 6bw5ptw7xao8 \_ web.8 nginx:latest worker1 Shutdown Shutdown 33 seconds ago
3.10 - Supprimer un Service
Pour supprimer un service il convient d'utiliser la commande docker service rm
docker@manager1:/$ docker service rm web web
docker@manager1:/$ docker service ls ID NAME MODE REPLICAS IMAGE PORTS
docker@manager1:/$ docker service inspect web [] Status: Error: no such service: web, Code: 1
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