swarm

DockerSwarm/Creaate-Swarm.adoc

@@ -168,6 +168,16 @@ docker node demote id
 
 == Manage nodes
 
+
+
+[NOTE]
+.INFO
+====
+
+This is a cluster management command, and must be executed on a swarm manager node.
+
+====
+
 - *docker node ls* 		List nodes in the swarm
 
 ----
@@ -176,9 +186,9 @@ docker node ls
 
 - *docker node demote* 	`_	Demote one or more nodes from manager in the swarm_`
 - *docker node inspect* `_	Display detailed information on one or more nodes_`
-- *docker node promote* `_	Promote one or more nodes to manager in the swarm_~
+- *docker node promote* `_	Promote one or more nodes to manager in the swarm_`
 - *docker node ps* 	`_	List tasks running on one or more nodes, defaults to current node_`
-- *docker node rm* 	`_	Remove one or more nodes from the swarm_~
+- *docker node rm* 	`_	Remove one or more nodes from the swarm_`
 - *docker node update* 	`_	Update a node_`
 - *docker node inspect* `_	Display detailed information on one or more nodes_`
 
@@ -244,3 +254,299 @@ docker node inspect id | jq -r '.[]["Status"]["State"]'
 ====
 
 
+
+
+== Deploy services and Tasks
+
+
+
+To deploy an application image when Docker Engine is in swarm mode, you *create a service.*
+
+A service is the image for a microservice within the context of some larger application. 
+
+Examples of services might include an HTTP server, a database, or any other type of executable program that you wish to run in a distributed environment.
+
+
+
+
+A *task* is the atomic unit of scheduling within a swarm. 
+
+When you declare a desired service state by creating or updating a service, the orchestrator realizes the desired state by scheduling tasks. 
+
+For instance, you define a service that instructs the orchestrator to keep three instances of an HTTP listener running at all times. 
+
+The orchestrator responds by creating three tasks. 
+
+Each task is a slot that the scheduler fills by spawning a container. 
+
+image:./services-diagram.png[alt="services"] +
+
+
+=== service vs  stack 
+
+- A *Service* defines one or more instances of a single image deployed on one or more machines (described by one entry in the services part of *yaml* files).
+
+- A *Stack* defines a group of heterogeneous services (described by the whole yaml file).
+
+
+The *docker service* command is used when managing individual service on a docker swarm cluster. 
+
+
+The *docker stack* command can be used to manage a multi-service application. 
+
+
+=== Build
+
+[NOTE]
+.INFO
+====
+
+This is a cluster management command, and must be executed on a swarm manager node.
+
+====
+
+==== Create yaml
+
+.yml example MPI (save as run.yml)
+[source,sh]
+----
+version: "3.8"
+
+services:
+
+  master:
+    image: image
+    user: root
+    environment:
+     # Pass environment variables to containers   CUSTOM
+     - PASSWORD=dgergergergerrfgwehrtsger
+     - PASSWORDVIEW=rtyrwtyrwftertgueteyserfy5e6ytrg
+     - SERVERROLE=master
+     - SERVERWEB=no
+     # Pass environment variables to containers  FROM ENGINE see inspect
+     - NODENAME={{.Node.Hostname}}
+     - NODEID={{.Node.ID}}
+     - SERVICEID={{.Service.ID}}
+     - SERVICENAME={{.Service.Name}}
+     - TASKID={{.Task.ID}}
+     - TASKNAME={{.Task.Name}}
+     - TASKREPID={{.Task.Slot}}
+    deploy:
+      # mode: global # see image  replica-vs-global
+      replicas: 1
+      placement:
+        max_replicas_per_node: 1
+        constraints:
+          - node.role == worker
+          #- node.labels.region == region1
+      resources:
+        limits:
+          cpus: '0.50'
+          memory: 500M
+        reservations:
+          cpus: '0.25'
+          memory: 200M
+      restart_policy:
+        condition: on-failure
+        delay: 5s
+        max_attempts: 5
+        window: 120s
+      update_config:
+        parallelism: 2
+        delay: 10s
+        order: stop-first
+    networks:
+      mpi2-net:
+    ports:
+      - "5580:80"
+      - "5588:8088"
+
+  slave:
+    image: image
+    user: root
+    environment:
+     - PASSWORD=rtyrthrthyrthyrtyrtyrty
+     - PASSWORDVIEW=rtyrtuyrtuyrt
+     - SERVERROLE=slave
+     - SERVERWEB=no
+     - NODENAME={{.Node.Hostname}}
+     - NODEID={{.Node.ID}}
+     - SERVICEID={{.Service.ID}}
+     - SERVICENAME={{.Service.Name}}
+     - TASKID={{.Task.ID}}
+     - TASKNAME={{.Task.Name}}
+     - TASKREPID={{.Task.Slot}}
+    deploy:
+      # mode: global # see image  replica-vs-global
+      replicas: 9
+      placement:
+        max_replicas_per_node: 1
+        constraints:
+          - node.role == worker
+          - node.labels.region == region2
+      resources:
+        limits:
+          cpus: '0.50'
+          memory: 500M
+        reservations:
+          cpus: '0.25'
+          memory: 200M
+      restart_policy:
+        condition: on-failure
+        delay: 5s
+        max_attempts: 5
+        window: 120s
+      update_config:
+        parallelism: 2
+        delay: 10s
+        order: stop-first
+    networks:
+      mpi2-net:
+    ports:
+      - "5581:80"
+      - "5590:8088"
+
+
+  web:
+    image: image
+    user: root
+    environment:
+     - SERVERROLE=web
+     - SERVERWEB=yes
+     - NODENAME={{.Node.Hostname}}
+     - NODEID={{.Node.ID}}
+     - SERVICEID={{.Service.ID}}
+     - SERVICENAME={{.Service.Name}}
+     - TASKID={{.Task.ID}}
+     - TASKNAME={{.Task.Name}}
+     - TASKREPID={{.Task.Slot}}
+    deploy:
+      # mode: global # see image  replica-vs-global
+      replicas: 1
+      placement:
+        constraints:
+          - node.role == worker
+          - node.labels.region == region3
+      resources:
+        limits:
+          cpus: '0.50'
+          memory: 500M
+        reservations:
+          cpus: '0.25'
+          memory: 200M
+      restart_policy:
+        condition: on-failure
+        delay: 5s
+        max_attempts: 5
+        window: 120s
+      update_config:
+        parallelism: 2
+        delay: 10s
+        order: stop-first
+    networks:
+      mpi2-net:
+    ports:
+      - "5598:80"
+      - "5599:8088"
+
+
+networks:
+  mpi2-net:
+
+
+
+----
+
+image:./replicated-vs-global.png[alt="replica-vs-global"] +
+
+
+
+[NOTE]
+.INFO
+====
+YAML (a recursive acronym for "YAML Ain't Markup Language") is a human-readable data-serialization language. 
+
+It is commonly used for configuration files and in applications where data is being stored or transmitted. 
+
+YAML targets many of the same communications applications as Extensible Markup Language (XML) but has a minimal syntax which intentionally differs from SGML  
+
+It uses Python-style indentation to indicate nesting
+
+From Wikipedia, the free encyclopedia +
+
+more: Learn YAML in five minutes!
+https://www.codeproject.com/Articles/1214409/Learn-YAML-in-five-minutes[^]
+
+====
+
+
+==== Build
+
+
+.build
+[source,sh]
+----
+docker stack deploy -c run.yml my_service
+----
+
+
+==== Lists services
+
+.List the services that are running as part of the specified stack.
+[source,sh]
+----
+docker stack services
+----
+
+
+
+.List  *ALL* services are running in the swarm.
+[source,sh]
+----
+docker service ls
+----
+
+
+
+
+==== Remove one or more stacks
+
+.Remove the stack from the swarm.
+[source,sh]
+----
+docker stack rm
+----
+
+.Removes the specified services from the swarm.
+[source,sh]
+----
+docker service rm
+----
+
+
+==== List tasks
+
+.List the tasks that are running as part of the specified services.
+[source,sh]
+----
+docker service ps
+----
+
+
+.List the tasks in the stack
+[source,sh]
+----
+docker stack ps
+----
+
+
+[NOTE]
+.INFO
+====
+Command-line completion (also tab completion) is a common feature of command-line interpreters, in which the program automatically fills in partially typed commands. 
+
+more info: https://en.wikipedia.org/wiki/Command-line_completion[^]
+
+====
+
+