github.com/jmitchell/nomad@v0.1.3-0.20151007230021-7ab84c2862d8/website/source/docs/drivers/exec.html.md (about)

     1  ---
     2  layout: "docs"
     3  page_title: "Drivers: Exec"
     4  sidebar_current: "docs-drivers-exec"
     5  description: |-
     6    The Exec task driver is used to run binaries using OS isolation primitives.
     7  ---
     8  
     9  # Fork/Exec Driver
    10  
    11  Name: `exec`
    12  
    13  The `exec` driver is used to simply execute a particular command for a task.
    14  This is the simplest driver and is extremely flexible. In particlar, because
    15  it can invoke any command, it can be used to call scripts or other wrappers
    16  which provide higher level features.
    17  
    18  ## Task Configuration
    19  
    20  The `exec` driver supports the following configuration in the job spec:
    21  
    22  * `command` - The command to execute. Must be provided.
    23  
    24  * `args` - The argument list to the command, space seperated. Optional.
    25  
    26  ## Client Requirements
    27  
    28  The `exec` driver can run on all supported operating systems but to provide
    29  proper isolation the client must be run as root on non-Windows operating systems.
    30  Further, to support cgroups, `/sys/fs/cgroups/` must be mounted.
    31  
    32  ## Client Attributes
    33  
    34  The `exec` driver will set the following client attributes:
    35  
    36  * `driver.exec` - This will be set to "1", indicating the
    37    driver is available.
    38  
    39  ## Resource Isolation
    40  
    41  The resource isolation provided varies by the operating system of
    42  the client and the configuration.
    43  
    44  On Linux, Nomad will use cgroups, namespaces, and chroot to isolate the
    45  resources of a process and as such the Nomad agent must be run as root.
    46  
    47  On Windows, the task driver will just execute the command with no additional
    48  resource isolation.