# There can only be a single job definition per file. This job is named # "example" so it will create a job with the ID and Name "example". # The "job" stanza is the top-most configuration option in the job # specification. A job is a declarative specification of tasks that Nomad # should run. Jobs have a globally unique name, one or many task groups, which # are themselves collections of one or many tasks. # # For more information and examples on the "job" stanza, please see # the online documentation at: # # https://www.nomadproject.io/docs/job-specification/job # job "example" { # The "region" parameter specifies the region in which to execute the job. # If omitted, this inherits the default region name of "global". # region = "global" # # The "datacenters" parameter specifies the list of datacenters which should # be considered when placing this task. This must be provided. datacenters = ["dc1"] # The "type" parameter controls the type of job, which impacts the scheduler's # decision on placement. This configuration is optional and defaults to # "service". For a full list of job types and their differences, please see # the online documentation. # # For more information, please see the online documentation at: # # https://www.nomadproject.io/docs/schedulers # type = "service" # The "constraint" stanza defines additional constraints for placing this job, # in addition to any resource or driver constraints. This stanza may be placed # at the "job", "group", or "task" level, and supports variable interpolation. # # For more information and examples on the "constraint" stanza, please see # the online documentation at: # # https://www.nomadproject.io/docs/job-specification/constraint # # constraint { # attribute = "${attr.kernel.name}" # value = "linux" # } # The "update" stanza specifies the update strategy of task groups. The update # strategy is used to control things like rolling upgrades, canaries, and # blue/green deployments. If omitted, no update strategy is enforced. The # "update" stanza may be placed at the job or task group. When placed at the # job, it applies to all groups within the job. When placed at both the job and # group level, the stanzas are merged with the group's taking precedence. # # For more information and examples on the "update" stanza, please see # the online documentation at: # # https://www.nomadproject.io/docs/job-specification/update # update { # The "max_parallel" parameter specifies the maximum number of updates to # perform in parallel. In this case, this specifies to update a single task # at a time. max_parallel = 1 # The "min_healthy_time" parameter specifies the minimum time the allocation # must be in the healthy state before it is marked as healthy and unblocks # further allocations from being updated. min_healthy_time = "10s" # The "healthy_deadline" parameter specifies the deadline in which the # allocation must be marked as healthy after which the allocation is # automatically transitioned to unhealthy. Transitioning to unhealthy will # fail the deployment and potentially roll back the job if "auto_revert" is # set to true. healthy_deadline = "3m" # The "progress_deadline" parameter specifies the deadline in which an # allocation must be marked as healthy. The deadline begins when the first # allocation for the deployment is created and is reset whenever an allocation # as part of the deployment transitions to a healthy state. If no allocation # transitions to the healthy state before the progress deadline, the # deployment is marked as failed. progress_deadline = "10m" # The "auto_revert" parameter specifies if the job should auto-revert to the # last stable job on deployment failure. A job is marked as stable if all the # allocations as part of its deployment were marked healthy. auto_revert = false # The "canary" parameter specifies that changes to the job that would result # in destructive updates should create the specified number of canaries # without stopping any previous allocations. Once the operator determines the # canaries are healthy, they can be promoted which unblocks a rolling update # of the remaining allocations at a rate of "max_parallel". # # Further, setting "canary" equal to the count of the task group allows # blue/green deployments. When the job is updated, a full set of the new # version is deployed and upon promotion the old version is stopped. canary = 0 } # The migrate stanza specifies the group's strategy for migrating off of # draining nodes. If omitted, a default migration strategy is applied. # # For more information on the "migrate" stanza, please see # the online documentation at: # # https://www.nomadproject.io/docs/job-specification/migrate # migrate { # Specifies the number of task groups that can be migrated at the same # time. This number must be less than the total count for the group as # (count - max_parallel) will be left running during migrations. max_parallel = 1 # Specifies the mechanism in which allocations health is determined. The # potential values are "checks" or "task_states". health_check = "checks" # Specifies the minimum time the allocation must be in the healthy state # before it is marked as healthy and unblocks further allocations from being # migrated. This is specified using a label suffix like "30s" or "15m". min_healthy_time = "10s" # Specifies the deadline in which the allocation must be marked as healthy # after which the allocation is automatically transitioned to unhealthy. This # is specified using a label suffix like "2m" or "1h". healthy_deadline = "5m" } # The "group" stanza defines a series of tasks that should be co-located on # the same Nomad client. Any task within a group will be placed on the same # client. # # For more information and examples on the "group" stanza, please see # the online documentation at: # # https://www.nomadproject.io/docs/job-specification/group # group "cache" { # The "count" parameter specifies the number of the task groups that should # be running under this group. This value must be non-negative and defaults # to 1. count = 1 # The "network" stanza specifies the network configuration for the allocation # including requesting port bindings. # # For more information and examples on the "network" stanza, please see # the online documentation at: # # https://www.nomadproject.io/docs/job-specification/network # network { port "db" { to = 6379 } } # The "service" stanza instructs Nomad to register this task as a service # in the service discovery engine, which is currently Nomad or Consul. This # will make the service discoverable after Nomad has placed it on a host and # port. # # For more information and examples on the "service" stanza, please see # the online documentation at: # # https://www.nomadproject.io/docs/job-specification/service # service { name = "redis-cache" tags = ["global", "cache"] port = "db" provider = "nomad" # The "check" stanza instructs Nomad to create a Consul health check for # this service. A sample check is provided here for your convenience; # uncomment it to enable it. The "check" stanza is documented in the # "service" stanza documentation. # check { # name = "alive" # type = "tcp" # interval = "10s" # timeout = "2s" # } } # The "restart" stanza configures a group's behavior on task failure. If # left unspecified, a default restart policy is used based on the job type. # # For more information and examples on the "restart" stanza, please see # the online documentation at: # # https://www.nomadproject.io/docs/job-specification/restart # restart { # The number of attempts to run the job within the specified interval. attempts = 2 interval = "30m" # The "delay" parameter specifies the duration to wait before restarting # a task after it has failed. delay = "15s" # The "mode" parameter controls what happens when a task has restarted # "attempts" times within the interval. "delay" mode delays the next # restart until the next interval. "fail" mode does not restart the task # if "attempts" has been hit within the interval. mode = "fail" } # The "ephemeral_disk" stanza instructs Nomad to utilize an ephemeral disk # instead of a hard disk requirement. Clients using this stanza should # not specify disk requirements in the resources stanza of the task. All # tasks in this group will share the same ephemeral disk. # # For more information and examples on the "ephemeral_disk" stanza, please # see the online documentation at: # # https://www.nomadproject.io/docs/job-specification/ephemeral_disk # ephemeral_disk { # When sticky is true and the task group is updated, the scheduler # will prefer to place the updated allocation on the same node and # will migrate the data. This is useful for tasks that store data # that should persist across allocation updates. # sticky = true # # Setting migrate to true results in the allocation directory of a # sticky allocation directory to be migrated. # migrate = true # # The "size" parameter specifies the size in MB of shared ephemeral disk # between tasks in the group. size = 300 } # The "affinity" stanza enables operators to express placement preferences # based on node attributes or metadata. # # For more information and examples on the "affinity" stanza, please # see the online documentation at: # # https://www.nomadproject.io/docs/job-specification/affinity # # affinity { # attribute specifies the name of a node attribute or metadata # attribute = "${node.datacenter}" # value specifies the desired attribute value. In this example Nomad # will prefer placement in the "us-west1" datacenter. # value = "us-west1" # weight can be used to indicate relative preference # when the job has more than one affinity. It defaults to 50 if not set. # weight = 100 # } # The "spread" stanza allows operators to increase the failure tolerance of # their applications by specifying a node attribute that allocations # should be spread over. # # For more information and examples on the "spread" stanza, please # see the online documentation at: # # https://www.nomadproject.io/docs/job-specification/spread # # spread { # attribute specifies the name of a node attribute or metadata # attribute = "${node.datacenter}" # targets can be used to define desired percentages of allocations # for each targeted attribute value. # # target "us-east1" { # percent = 60 # } # target "us-west1" { # percent = 40 # } # } # The "task" stanza creates an individual unit of work, such as a Docker # container, web application, or batch processing. # # For more information and examples on the "task" stanza, please see # the online documentation at: # # https://www.nomadproject.io/docs/job-specification/task # task "redis" { # The "driver" parameter specifies the task driver that should be used to # run the task. driver = "docker" # The "config" stanza specifies the driver configuration, which is passed # directly to the driver to start the task. The details of configurations # are specific to each driver, so please see specific driver # documentation for more information. config { image = "redis:7" ports = ["db"] # The "auth_soft_fail" configuration instructs Nomad to try public # repositories if the task fails to authenticate when pulling images # and the Docker driver has an "auth" configuration block. auth_soft_fail = true } # The "artifact" stanza instructs Nomad to download an artifact from a # remote source prior to starting the task. This provides a convenient # mechanism for downloading configuration files or data needed to run the # task. It is possible to specify the "artifact" stanza multiple times to # download multiple artifacts. # # For more information and examples on the "artifact" stanza, please see # the online documentation at: # # https://www.nomadproject.io/docs/job-specification/artifact # # artifact { # source = "http://foo.com/artifact.tar.gz" # options { # checksum = "md5:c4aa853ad2215426eb7d70a21922e794" # } # } # The "logs" stanza instructs the Nomad client on how many log files and # the maximum size of those logs files to retain. Logging is enabled by # default, but the "logs" stanza allows for finer-grained control over # the log rotation and storage configuration. # # For more information and examples on the "logs" stanza, please see # the online documentation at: # # https://www.nomadproject.io/docs/job-specification/logs # # logs { # max_files = 10 # max_file_size = 15 # } # The "resources" stanza describes the requirements a task needs to # execute. Resource requirements include memory, cpu, and more. # This ensures the task will execute on a machine that contains enough # resource capacity. # # For more information and examples on the "resources" stanza, please see # the online documentation at: # # https://www.nomadproject.io/docs/job-specification/resources # resources { cpu = 500 # 500 MHz memory = 256 # 256MB } # The "template" stanza instructs Nomad to manage a template, such as # a configuration file or script. This template can optionally pull data # from Consul or Vault to populate runtime configuration data. # # For more information and examples on the "template" stanza, please see # the online documentation at: # # https://www.nomadproject.io/docs/job-specification/template # # template { # data = "---\nkey: {{ key \"service/my-key\" }}" # destination = "local/file.yml" # change_mode = "signal" # change_signal = "SIGHUP" # } # The "template" stanza can also be used to create environment variables # for tasks that prefer those to config files. The task will be restarted # when data pulled from Consul or Vault changes. # # template { # data = "KEY={{ key \"service/my-key\" }}" # destination = "local/file.env" # env = true # } # The "vault" stanza instructs the Nomad client to acquire a token from # a HashiCorp Vault server. The Nomad servers must be configured and # authorized to communicate with Vault. By default, Nomad will inject # The token into the job via an environment variable and make the token # available to the "template" stanza. The Nomad client handles the renewal # and revocation of the Vault token. # # For more information and examples on the "vault" stanza, please see # the online documentation at: # # https://www.nomadproject.io/docs/job-specification/vault # # vault { # policies = ["cdn", "frontend"] # change_mode = "signal" # change_signal = "SIGHUP" # } # Controls the timeout between signalling a task it will be killed # and killing the task. If not set a default is used. # kill_timeout = "20s" } } }