Docker Mastery: Section 7 - (Swarm) create first service and scale it locally
Tags: swarm, udemy-docker
- section7-60
Udemy
Create your first service and scale it locally
- 看現在 swarm 狀態
docker info
- 初始化 swarm
docker swarm init
PS E:\> docker swarm init Swarm initialized: current node (ffaok4w0uqwb6cgt25luwfv1v) is now a manager. To add a worker to this swarm, run the following command: docker swarm join --token SWMTKN-1-2e1r4xj3d00pcqpm60wv2fqk4if1umthgyey6l99b84rjj1uy2-f3zi7t6ec3xq2clh4jmdbc1l2 192.168.65.3:2377 To add a manager to this swarm, run 'docker swarm join-token manager' and follow the instructions. PS E:\>
Docker swarm init: What Just Happened?
- Lots of PKI and security automation
- Root Signing Certificate created for our Swarm
- Certificate is issued for first Manager node
- Join tokens are created
- Raft database created to store root CA, configs and secrets
- Encrypted by default on disk (1.13+)
- No need for another key/value system to hold orchestration/secrets
- Replicate logs amongst Managers via mutual TLS in “control plane”
Swarm cli
-
docker node lsCONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES PS E:\> docker node ls ID HOSTNAME STATUS AVAILABILITY MANAGER STATUS ENGINE VERSION ffaok4w0uqwb6cgt25luwfv1v * docker-desktop Ready Active Leader 19.03.5 -
docker node --helpPS E:\> docker node --help Usage: docker node COMMAND Manage Swarm nodes Commands: demote Demote one or more nodes from manager in the swarm inspect Display detailed information on one or more nodes ls List nodes in the swarm promote Promote one or more nodes to manager in the swarm ps List tasks running on one or more nodes, defaults to current node rm Remove one or more nodes from the swarm update Update a node Run 'docker node COMMAND --help' for more information on a command. -
docker swarm --helpPS E:\> docker swarm --help Usage: docker swarm COMMAND Manage Swarm Commands: ca Display and rotate the root CA init Initialize a swarm join Join a swarm as a node and/or manager join-token Manage join tokens leave Leave the swarm unlock Unlock swarm unlock-key Manage the unlock key update Update the swarm Run 'docker swarm COMMAND --help' for more information on a command. -
docker service --help- service in swarm replace
docker run
PS E:\> docker service --help Usage: docker service COMMAND Manage services Commands: create Create a new service inspect Display detailed information on one or more services logs Fetch the logs of a service or task ls List services ps List the tasks of one or more services rm Remove one or more services rollback Revert changes to a service's configuration scale Scale one or multiple replicated services update Update a service Run 'docker service COMMAND --help' for more information on a command. - service in swarm replace
Swarm Orchestration
-
docker service create alpine ping 8.8.8.8 -
docker service ls- REPLICAS: [有幾個正在跑]/[定義總共有幾個]
PS E:\> docker service ls ID NAME MODE REPLICAS IMAGE PORTS w16lr30xhmsv tender_goldberg replicated 1/1 alpine:latest -
docker service ps <name/id>-
docker service ps tender_goldberg- showing tasks or containers of the service
-
PS E:\> docker service ps tender_goldberg ID NAME IMAGE NODE DESIRED STATE CURRENT STATE ERROR PORTS sswdox7tf8c0 tender_goldberg.1 alpine:latest docker-desktop Running Running 15 minutes ago
-
-
跑回去，單純看 docker container ls 的狀態
-
docker container ls -
PS E:\> docker container ls CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES a8a22ee6fdcb alpine:latest "ping 8.8.8.8" 17 minutes ago Up 17 minutes tender_goldberg.1.sswdox7tf8c0kkkaelexywhhq
-
-
scale up the service
-
docker service update <ID/Name> --replicas 3 -
先看 service id/name :
docker service lsdocker servcie update w16lr30xhmsv --replicas 3
-
PS E:\> docker service ls ID NAME MODE REPLICAS IMAGE PORTS w16lr30xhmsv tender_goldberg replicated 1/1 alpine:latest PS E:\> docker service update w16lr30xhmsv --replicas 3 w16lr30xhmsv overall progress: 3 out of 3 tasks 1/3: running 2/3: running 3/3: running verify: Service converged -
看
docker service ls,docker service ps <servcieID/serviceName>anddocker container ls -
PS E:\> docker service ls ID NAME MODE REPLICAS IMAGE PORTS w16lr30xhmsv tender_goldberg replicated 3/3 alpine:latest PS E:\> docker service ps tender_goldberg ID NAME IMAGE NODE DESIRED STATE CURRENT STATE ERROR PORTS sswdox7tf8c0 tender_goldberg.1 alpine:latest docker-desktop Running Running 31 minutes ago ufskmhuj4wj1 tender_goldberg.2 alpine:latest docker-desktop Running Running 4 minutes ago ljbe1ru4f6t7 tender_goldberg.3 alpine:latest docker-desktop Running Running 4 minutes ago PS E:\> docker container ls CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES b8744dc7ce3e alpine:latest "ping 8.8.8.8" 5 minutes ago Up 5 minutes tender_goldberg.3.ljbe1ru4f6t7k7m767nq3obbd 31a05e27c24f alpine:latest "ping 8.8.8.8" 5 minutes ago Up 5 minutes tender_goldberg.2.ufskmhuj4wj15qfz911i05684 a8a22ee6fdcb alpine:latest "ping 8.8.8.8" 31 minutes ago Up 31 minutes tender_goldberg.1.sswdox7tf8c0kkkaelexywhhq
-
Update CLI
-
docker update --help-
cmd for docker run conatienr to update certain variables on a running container without having to kill it or restart it
-
PS E:\> docker update --help Usage: docker update [OPTIONS] CONTAINER [CONTAINER...] Update configuration of one or more containers Options: --blkio-weight uint16 Block IO (relative weight), between 10 and 1000, or 0 to disable (default 0) --cpu-period int Limit CPU CFS (Completely Fair Scheduler) period --cpu-quota int Limit CPU CFS (Completely Fair Scheduler) quota --cpu-rt-period int Limit the CPU real-time period in microseconds --cpu-rt-runtime int Limit the CPU real-time runtime in microseconds -c, --cpu-shares int CPU shares (relative weight) --cpus decimal Number of CPUs --cpuset-cpus string CPUs in which to allow execution (0-3, 0,1) --cpuset-mems string MEMs in which to allow execution (0-3, 0,1) --kernel-memory bytes Kernel memory limit -m, --memory bytes Memory limit --memory-reservation bytes Memory soft limit --memory-swap bytes Swap limit equal to memory plus swap: '-1' to enable unlimited swap --pids-limit int Tune container pids limit (set -1 for unlimited) --restart string Restart policy to apply when a container exits
-
-
docker service update --help-
有超多選項，因為 Swarm Service 本身就是設計成可以 to replace conatiners, update services without taking all things down
-
PS E:\> docker service update --help Usage: docker service update [OPTIONS] SERVICE Update a service Options: --args command Service command args --config-add config Add or update a config file on a service --config-rm list Remove a configuration file --constraint-add list Add or update a placement constraint --constraint-rm list Remove a constraint --container-label-add list Add or update a container label --container-label-rm list Remove a container label by its key --credential-spec credential-spec Credential spec for managed service account (Windows only) -d, --detach Exit immediately instead of waiting for the service to converge --dns-add list Add or update a custom DNS server --dns-option-add list Add or update a DNS option --dns-option-rm list Remove a DNS option --dns-rm list Remove a custom DNS server --dns-search-add list Add or update a custom DNS search domain --dns-search-rm list Remove a DNS search domain --endpoint-mode string Endpoint mode (vip or dnsrr) --entrypoint command Overwrite the default ENTRYPOINT of the image --env-add list Add or update an environment variable --env-rm list Remove an environment variable --force Force update even if no changes require it --generic-resource-add list Add a Generic resource --generic-resource-rm list Remove a Generic resource --group-add list Add an additional supplementary user group to the container --group-rm list Remove a previously added supplementary user group from the container --health-cmd string Command to run to check health --health-interval duration Time between running the check (ms|s|m|h) --health-retries int Consecutive failures needed to report unhealthy --health-start-period duration Start period for the container to initialize before counting retries towards unstable (ms|s|m|h) --health-timeout duration Maximum time to allow one check to run (ms|s|m|h) --host-add list Add a custom host-to-IP mapping (host:ip) --host-rm list Remove a custom host-to-IP mapping (host:ip) --hostname string Container hostname --image string Service image tag --init Use an init inside each service container to forward signals and reap processes --isolation string Service container isolation mode --label-add list Add or update a service label --label-rm list Remove a label by its key --limit-cpu decimal Limit CPUs --limit-memory bytes Limit Memory --log-driver string Logging driver for service --log-opt list Logging driver options --mount-add mount Add or update a mount on a service --mount-rm list Remove a mount by its target path --network-add network Add a network --network-rm list Remove a network --no-healthcheck Disable any container-specified HEALTHCHECK --no-resolve-image Do not query the registry to resolve image digest and supported platforms --placement-pref-add pref Add a placement preference --placement-pref-rm pref Remove a placement preference --publish-add port Add or update a published port --publish-rm port Remove a published port by its target port -q, --quiet Suppress progress output --read-only Mount the container's root filesystem as read only --replicas uint Number of tasks --replicas-max-per-node uint Maximum number of tasks per node (default 0 = unlimited) --reserve-cpu decimal Reserve CPUs --reserve-memory bytes Reserve Memory --restart-condition string Restart when condition is met ("none"|"on-failure"|"any") --restart-delay duration Delay between restart attempts (ns|us|ms|s|m|h) --restart-max-attempts uint Maximum number of restarts before giving up --restart-window duration Window used to evaluate the restart policy (ns|us|ms|s|m|h) --rollback Rollback to previous specification --rollback-delay duration Delay between task rollbacks (ns|us|ms|s|m|h) --rollback-failure-action string Action on rollback failure ("pause"|"continue") --rollback-max-failure-ratio float Failure rate to tolerate during a rollback --rollback-monitor duration Duration after each task rollback to monitor for failure (ns|us|ms|s|m|h) --rollback-order string Rollback order ("start-first"|"stop-first") --rollback-parallelism uint Maximum number of tasks rolled back simultaneously (0 to roll back all at once) --secret-add secret Add or update a secret on a service --secret-rm list Remove a secret --stop-grace-period duration Time to wait before force killing a container (ns|us|ms|s|m|h) --stop-signal string Signal to stop the container --sysctl-add list Add or update a Sysctl option --sysctl-rm list Remove a Sysctl option -t, --tty Allocate a pseudo-TTY --update-delay duration Delay between updates (ns|us|ms|s|m|h) --update-failure-action string Action on update failure ("pause"|"continue"|"rollback") --update-max-failure-ratio float Failure rate to tolerate during an update --update-monitor duration Duration after each task update to monitor for failure (ns|us|ms|s|m|h) --update-order string Update order ("start-first"|"stop-first") --update-parallelism uint Maximum number of tasks updated simultaneously (0 to update all at once) -u, --user string Username or UID (format: <name|uid>[:<group|gid>]) --with-registry-auth Send registry authentication details to swarm agents -w, --workdir string Working directory inside the container
-
Swarm 會確保 contaienr 正常運作！
-
關掉某 container 的時候，會自動重啟！
-
PS E:\> docker service ls ID NAME MODE REPLICAS IMAGE PORTS w16lr30xhmsv tender_goldberg replicated 3/3 alpine:latest PS E:\> docker rm -f tender_goldberg.3.ljbe1ru4f6t7k7m767nq3obbd Error: No such container: tender_goldberg.3.ljbe1ru4f6t7k7m767nq3obbd PS E:\> docker container ls CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 444518744d3c alpine:latest "ping 8.8.8.8" 31 seconds ago Up 26 seconds tender_goldberg.3.j9rvj0l5jd8pnflt84lja7w6l 31a05e27c24f alpine:latest "ping 8.8.8.8" 26 minutes ago Up 26 minutes tender_goldberg.2.ufskmhuj4wj15qfz911i05684 a8a22ee6fdcb alpine:latest "ping 8.8.8.8" 52 minutes ago Up 52 minutes tender_goldberg.1.sswdox7tf8c0kkkaelexywhhq PS E:\> docker rm -f tender_goldberg.3.j9rvj0l5jd8pnflt84lja7w6l tender_goldberg.3.j9rvj0l5jd8pnflt84lja7w6l PS E:\> docker service ls ID NAME MODE REPLICAS IMAGE PORTS w16lr30xhmsv tender_goldberg replicated 3/3 alpine:latest PS E:\> docker service ps tendser_goldberg no such service: tendser_goldberg PS E:\> docker service ps tender_goldberg ID NAME IMAGE NODE DESIRED STATE CURRENT STATE ERROR PORTS sswdox7tf8c0 tender_goldberg.1 alpine:latest docker-desktop Running Running 53 minutes ago ufskmhuj4wj1 tender_goldberg.2 alpine:latest docker-desktop Running Running 27 minutes ago os9sui81ejos tender_goldberg.3 alpine:latest docker-desktop Running Running 24 seconds ago j9rvj0l5jd8p \_ tender_goldberg.3 alpine:latest docker-desktop Shutdown Failed 29 seconds ago "task: non-zero exit (137)" ljbe1ru4f6t7 \_ tender_goldberg.3 alpine:latest docker-desktop Shutdown Failed about a minute ago "task: non-zero exit (137)" -
關掉 Service
-
docker service rm <name/ID> -
PS E:\> docker service ls ID NAME MODE REPLICAS IMAGE PORTS w16lr30xhmsv tender_goldberg replicated 3/3 alpine:latest PS E:\> docker service rm tender_goldberg tender_goldberg PS E:\> docker container ls CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
-