open-nomad/website/source/docs/commands/plan.html.md.erb

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---
layout: "docs"
page_title: "Commands: plan"
sidebar_current: "docs-commands-plan"
description: >
The plan command is used to dry-run a job update to determine its effects.
---
# 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](/docs/job-specification/index.html) format.
## Usage
```
nomad plan [options] <path>
```
The plan command requires a single argument, specifying the path to a file
containing a [HCL job specification](/docs/job-specification/index.html). 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`](https://github.com/hashicorp/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`](/docs/commands/run.html#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
<%= partial "docs/commands/_general_options" %>
## Plan Options
* `-diff`: Determines whether the diff between the remote job and planned job is
shown. Defaults to true.
* `-policy-override`: Sets the flag to force override any soft mandatory Sentinel policies.
* `-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 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.
```