anchor.diff:  1. Provisions and configures the VM for the errand
   1. Installs the errand code and all required packages and templates
   1. Runs the processes specified by the errand
  -1. Sends all output of the errand to the BOSH CLI for output to the screen
  +1. Sends all output of the errand to the BOSH CLI for output
   1. Releases the deployment lock
   1. Release the VM back into the resource pool
   
  
positive.code: resource pool for a BOSH deployment with errands must include one additional VM
  per errand.
  
  To run an errand, use `bosh run errand ERRAND-NAME`. ERRAND-NAME must be an
  errand job name provided in the deployment manifest.
  
  Example:
  
  
negative.code: The `bosh cancel errand` command terminates the errand process, releases the
  deployment lock, and returns the errand VM to the resource pool.
  
  #### <a id="errand-logging"></a>Errand Logging ####
  
  BOSH only logs errand output if the output is greater than 1 MB in size.
  By default, BOSH streams smaller errand output, stdout, and stderr to the screen.
  
  When BOSH [runs an errand](#errand-running), BOSH provisions and configures a VM for the errand.
  When the errand completes, BOSH releases the VM back into the resource pool.
  Once the VM has been released back into the resource pool, you cannot access any log files or screen output on the VM.
  
  To save log files and screen output from a BOSH errand VM:
  
  1. In the BOSH errand script, redirect stdout and stderr to a log file.
  1. Using the BOSH CLI, run `bosh errand` with the `--download-logs` option to download the log files.
  
      By default, BOSH downloads the logs to your present working directory.
      Use the `--logs-dir destination_directory` option to change this
      directory.
  
      <pre class='terminal'>
      $ run errand SampleErrand --download-logs --logs-dir ~/workspace/SampleLogDirectory
      </pre>
  
  ## <a id="errand-running"></a>Warnings and Additional Information ##
  
  * Errands do not have a notion of persistence. Persistent disk migration for errands is not supported.
  * Whenever an errand runs, BOSH initiates a deployment lock. This lock prevent all other deploys. Additionally, the BOSH CLI `cck` command is unavailable, and the health monitor does not scan and fix current deployments during the duration of the errand.
  * Currently, BOSH limits errand output to 1 MB. BOSH discards errand output greater than 1 MB.