» Command: plan

The plan command can be used to envoke the scheduler in a dry-run mode with new jobs or when updating existing jobs to determine what would happen if the job is submitted. Job files must conform to the job specification format.

» Usage 

nomad plan [options] <path>

The plan command requires a single argument, specifying the path to a file containing a HCL job specification. This file will be read and the resulting parsed job will be validated. If the supplied path is "-", the job file is read from STDIN. Otherwise it is read from the file at the supplied path or downloaded and read from URL specified. Nomad downloads the job file using go-getter and supports go-getter syntax.

Plan invokes a dry-run of the scheduler to determine the effects of submitting either a new or updated version of a job. The plan will not result in any changes to the cluster but gives insight into whether the job could be run successfully and how it would affect existing allocations.

A job modify index is returned with the plan. This value can be used when submitting the job using nomad run -check-index, which will check that the job was not modified between the plan and run command before invoking the scheduler. This ensures the job has not been modified since the plan.

A structured diff between the local and remote job is displayed to give insight into what the scheduler will attempt to do and why.

If the job has specified the region, the -region flag and NOMAD_REGION environment variable are overridden and the job's region is used.

Plan will return one of the following exit codes:

  • 0: No allocations created or destroyed.
  • 1: Allocations created or destroyed.
  • 255: Error determining plan results.

» General Options

  • -address=<addr>: The address of the Nomad server. Overrides the NOMAD_ADDR environment variable if set. Defaults to http://127.0.0.1:4646.

  • -region=<region>: The region of the Nomad server to forward commands to. Overrides the NOMAD_REGION environment variable if set. Defaults to the Agent's local region.

  • -no-color: Disables colored command output.

  • -ca-cert=<path>: Path to a PEM encoded CA cert file to use to verify the Nomad server SSL certificate. Overrides the NOMAD_CACERT environment variable if set.

  • -ca-path=<path>: Path to a directory of PEM encoded CA cert files to verify the Nomad server SSL certificate. If both -ca-cert and -ca-path are specified, -ca-cert is used. Overrides the NOMAD_CAPATH environment variable if set.

  • -client-cert=<path>: Path to a PEM encoded client certificate for TLS authentication to the Nomad server. Must also specify -client-key. Overrides the NOMAD_CLIENT_CERT environment variable if set.

  • -client-key=<path>: Path to an unencrypted PEM encoded private key matching the client certificate from -client-cert. Overrides the NOMAD_CLIENT_KEY environment variable if set.

  • -tls-skip-verify: Do not verify TLS certificate. This is highly not recommended. Verification will also be skipped if NOMAD_SKIP_VERIFY is set.

» Plan Options

  • -diff: Determines whether the diff between the remote job and planned job is shown. Defaults to true.

  • -verbose: Increase diff verbosity.

» Examples

Plan a new job that has not been previously submitted:

$ nomad run job1.nomad
nomad plan example.nomad
+ Job: "example"
+ Task Group: "cache" (1 create)
  + Task: "redis" (forces create)

Scheduler dry-run:
- All tasks successfully allocated.

Job Modify Index: 0
To submit the job with version verification run:

nomad run -check-index 0 example.nomad

When running the job with the check-index flag, the job will only be run if the
server side version matches the job modify index returned. If the index has
changed, another user has modified the job and the plan's results are
potentially invalid.

Increase the count of an existing without sufficient cluster capacity:

$ nomad plan example.nomad
+/- Job: "example"
+/- Task Group: "cache" (7 create, 1 in-place update)
  +/- Count: "1" => "8" (forces create)
      Task: "redis"

Scheduler dry-run:
- WARNING: Failed to place all allocations.
  Task Group "cache" (failed to place 3 allocations):
    * Resources exhausted on 1 nodes
    * Dimension "cpu exhausted" exhausted on 1 nodes

Job Modify Index: 15
To submit the job with version verification run:

nomad run -check-index 15 example.nomad

When running the job with the check-index flag, the job will only be run if the
server side version matches the job modify index returned. If the index has
changed, another user has modified the job and the plan's results are
potentially invalid.

Update an existing job such that it would cause a rolling update:

$ nomad plan example.nomad
+/- Job: "example"
+/- Task Group: "cache" (3 create/destroy update)
  +/- Task: "redis" (forces create/destroy update)
    +/- Config {
      +/- image:           "redis:2.8" => "redis:3.2"
          port_map[0][db]: "6379"
    }

Scheduler dry-run:
- All tasks successfully allocated.
- Rolling update, next evaluation will be in 10s.

Job Modify Index: 7
To submit the job with version verification run:

nomad run -check-index 7 example.nomad

When running the job with the check-index flag, the job will only be run if the
server side version matches the job modify index returned. If the index has
changed, another user has modified the job and the plan's results are
potentially invalid.

Add a task to the task group using verbose mode:

$ nomad plan -verbose example.nomad
+/- Job: "example"
+/- Task Group: "cache" (3 create/destroy update)
  + Task: "my-website" (forces create/destroy update)
    + Driver:      "docker"
    + KillTimeout: "5000000000"
    + Config {
      + image:            "node:6.2"
      + port_map[0][web]: "80"
    }
    + Resources {
      + CPU:      "500"
      + DiskMB:   "300"
      + IOPS:     "0"
      + MemoryMB: "256"
      + Network {
        + MBits: "10"
        + Dynamic Port {
          + Label: "web"
        }
      }
    }
    + LogConfig {
      + MaxFileSizeMB: "10"
      + MaxFiles:      "10"
    }
    + Service {
      + Name:      "website"
      + PortLabel: "web"
      + Check {
          Command:  ""
        + Interval: "10000000000"
        + Name:     "alive"
          Path:     ""
          Protocol: ""
        + Timeout:  "2000000000"
        + Type:     "tcp"
      }
    }
    Task: "redis"

Scheduler dry-run:
- All tasks successfully allocated.
- Rolling update, next evaluation will be in 10s.

Job Modify Index: 7
To submit the job with version verification run:

nomad run -check-index 7 example.nomad

When running the job with the check-index flag, the job will only be run if the
server side version matches the job modify index returned. If the index has
changed, another user has modified the job and the plan's results are
potentially invalid.