Bump minimum required rkt version; update docs

Make section names match between docker and rkt

CHANGELOG.md

@@ -13,6 +13,7 @@ IMPROVEMENTS:
   * driver: Export `NOMAD_JOB_NAME` environment variable [GH-1804]
   * driver/docker: Support Docker volumes [GH-1767]
   * driver/docker: Allow Docker logging to be configured [GH-1767]
+  * driver/rkt: Support rkt volumes (rkt >= 1.0.0 required) [GH-1812]
 
 BUG FIXES:
   * agent: Handle the SIGPIPE signal preventing panics on journalctl restarts

client/driver/rkt.go

@@ -38,7 +38,7 @@ const (
 	// minRktVersion is the earliest supported version of rkt. rkt added support
 	// for CPU and memory isolators in 0.14.0. We cannot support an earlier
 	// version to maintain an uniform interface across all drivers
-	minRktVersion = "0.14.0"
+	minRktVersion = "1.0.0"
 
 	// The key populated in the Node Attributes to indicate the presence of the
 	// Rkt driver
@@ -47,6 +47,9 @@ const (
 	// rktVolumesConfigOption is the key for enabling the use of custom
 	// bind volumes.
 	rktVolumesConfigOption = "rkt.volumes.enabled"
+
+	// rktCmd is the command rkt is installed as.
+	rktCmd = "rkt"
 )
 
 // RktDriver is a driver for running images via Rkt
@@ -147,7 +150,7 @@ func (d *RktDriver) Fingerprint(cfg *config.Config, node *structs.Node) (bool, e
 		return false, nil
 	}
 
-	outBytes, err := exec.Command("rkt", "version").Output()
+	outBytes, err := exec.Command(rktCmd, "version").Output()
 	if err != nil {
 		delete(node.Attributes, rktDriverAttr)
 		return false, nil
@@ -168,7 +171,7 @@ func (d *RktDriver) Fingerprint(cfg *config.Config, node *structs.Node) (bool, e
 	minVersion, _ := version.NewVersion(minRktVersion)
 	currentVersion, _ := version.NewVersion(node.Attributes["driver.rkt.version"])
 	if currentVersion.LessThan(minVersion) {
-		// Do not allow rkt < 0.14.0
+		// Do not allow ancient rkt versions
 		d.logger.Printf("[WARN] driver.rkt: please upgrade rkt to a version >= %s", minVersion)
 		node.Attributes[rktDriverAttr] = "0"
 	}
@@ -203,7 +206,7 @@ func (d *RktDriver) Start(ctx *ExecContext, task *structs.Task) (DriverHandle, e
 	insecure := false
 	if trustPrefix != "" {
 		var outBuf, errBuf bytes.Buffer
-		cmd := exec.Command("rkt", "trust", "--skip-fingerprint-review=true", fmt.Sprintf("--prefix=%s", trustPrefix), fmt.Sprintf("--debug=%t", debug))
+		cmd := exec.Command(rktCmd, "trust", "--skip-fingerprint-review=true", fmt.Sprintf("--prefix=%s", trustPrefix), fmt.Sprintf("--debug=%t", debug))
 		cmd.Stdout = &outBuf
 		cmd.Stderr = &errBuf
 		if err := cmd.Run(); err != nil {
@@ -331,7 +334,7 @@ func (d *RktDriver) Start(ctx *ExecContext, task *structs.Task) (DriverHandle, e
 		return nil, fmt.Errorf("failed to set executor context: %v", err)
 	}
 
-	absPath, err := GetAbsolutePath("rkt")
+	absPath, err := GetAbsolutePath(rktCmd)
 	if err != nil {
 		return nil, err
 	}

website/source/docs/drivers/docker.html.md

@@ -315,7 +315,7 @@ Some networking modes like `container` or `none` will require coordination
 outside of Nomad. First-class support for these options may be improved later
 through Nomad plugins or dynamic job configuration.
 
-## Host Requirements
+## Client Requirements
 
 Nomad requires Docker to be installed and running on the host alongside the
 Nomad agent. Nomad was developed against Docker `1.8.2` and `1.9`.
@@ -333,7 +333,7 @@ user to the `docker` group so you can run Nomad without root:
 For the best performance and security features you should use recent versions
 of the Linux Kernel and Docker daemon.
 
-## Agent Configuration
+## Client Configuration
 
 The `docker` driver has the following [client configuration
 options](/docs/agent/config.html#options):
@@ -392,7 +392,7 @@ client {
 }
 ```
 
-## Agent Attributes
+## Client Attributes
 
 The `docker` driver will set the following client attributes:
 

website/source/docs/drivers/rkt.html.md

@@ -75,10 +75,15 @@ The `rkt` driver supports the following configuration in the job spec:
 
 * `debug` - (Optional) Enable rkt command debug option.
 
-## Task Directories
+* `volumes` - (Optional) A list of `host_path:container_path` strings to bind
+  host paths to container paths. Can only be run on clients with the
+  `rkt.volumes.enabled` option set to true.
 
-The `rkt` driver currently does not support mounting of the `alloc/` and `local/` directories.
-Once support is added, version `v0.10.0` or above of `rkt` will be required.
+    ```hcl
+    config {
+      volumes = ["/path/on/host:/path/in/container"]
+    }
+    ```
 
 ## Client Requirements
 
@@ -87,15 +92,24 @@ The `trust_prefix` must be accessible by the node running Nomad. This can be an
 internal source, private to your cluster, but it must be reachable by the client
 over HTTP.
 
+## Client Configuration
+
+The `rkt` driver has the following [client configuration
+options](/docs/agent/config.html#options):
+
+* `rkt.volumes.enabled`: Defaults to `false`. Allows tasks to bind host paths
+  (`volumes`) inside their container.  Disabled by default as it removes the
+  isolation between containers' data.
+
 ## Client Attributes
 
 The `rkt` driver will set the following client attributes:
 
 * `driver.rkt` - Set to `1` if rkt is found on the host node. Nomad determines
-this by executing `rkt version` on the host and parsing the output
-* `driver.rkt.version` - Version of `rkt` eg: `0.8.1`. Note that the minimum required
-version is `0.14.0`
-* `driver.rkt.appc.version` - Version of `appc` that `rkt` is using eg: `0.8.1`
+  this by executing `rkt version` on the host and parsing the output
+* `driver.rkt.version` - Version of `rkt` eg: `1.1.0`. Note that the minimum required
+  version is `1.0.0`
+* `driver.rkt.appc.version` - Version of `appc` that `rkt` is using eg: `1.1.0`
 
 Here is an example of using these properties in a job file:
 
@@ -105,7 +119,7 @@ job "docs" {
   constraint {
     attribute = "${driver.rkt.version}"
     operator  = ">"
-    value     = "0.8"
+    value     = "1.2"
   }
 }
 ```