Author: arkurth
Date: Wed Jul 22 16:23:04 2015
New Revision: 1692299
URL: http://svn.apache.org/r1692299
Log:
Changed script path to updated location as of 2.4.2, improved explaination
Modified:
vcl/site/trunk/content/docs/vclPostScripts.mdtext
Modified: vcl/site/trunk/content/docs/vclPostScripts.mdtext
URL:
http://svn.apache.org/viewvc/vcl/site/trunk/content/docs/vclPostScripts.mdtext?rev=1692299&r1=1692298&r2=1692299&view=diff
==============================================================================
--- vcl/site/trunk/content/docs/vclPostScripts.mdtext (original)
+++ vcl/site/trunk/content/docs/vclPostScripts.mdtext Wed Jul 22 16:23:04 2015
@@ -16,21 +16,67 @@ Notice: Licensed to the Apache Softwa
specific language governing permissions and limitations
under the License.
-VCL post scripts allow for customization after a node is loaded or reserved.
If these scripts exists in the default location they will be excuted at their
designated times. These scripts are often used for Cluster on demand or for
handling custom tasks that are local to the node.
+Scripts may be saved within Linux VCL images which are automatically executed
at specific stages of the VCL
+reservation process. The scripts are added by the image creator prior to
saving the image. They must be
+located and named exactly as specified below.
-The scripts are:
+## Post-Load
+####Script: /usr/local/vcl/vcl_post_load
- 1. vcl_post_load
- - File location in Linux /etc/init.d/vcl_post_load
- - File location in Windows is SYSTEMROOT, usually
C:\Windows\vcl_post_load.cmd
- - Executed after a node is loaded during the post_load process during a
new reservation or reload
- - Created by the image owner
- - Ideal for editing configuration files or registering OS
-
- 2. vcl_post_reserve
- - Linux File location /etc/init.d/vcl_post_reserve
- - Windows File location is SYSTEMROOT, usually
C:\Windows\vcl_post_reserve.cmd
- - Executed during an active reservation, when user hits "Connect" button
- - Created by the image owner
- - Ideal for making custom changes to configuration files, such as Cluster
on Demand or starting services
-
\ No newline at end of file
+The post-load script will be executed every time a compute node is loaded,
meaning:
+
+* Whether or not the compute node is assigned to a user's reservation
+* After a user's reservation ends and the compute node is automatically
reloaded with another image
+* After a compute node is reloaded with a specific image via the Manage
Computers utility
+
+The post-load script is executed after all of the standard *post-load* steps
are performed via SSH by the
+management node's vcld process. For Linux images, these steps include:
+
+* Secure the firewall to only allow access from the management node
+* Configure the SSH service so access is only permitted from the management
node
+* Randomize the root password
+* Set the node's hostname
+
+It is **important** to recognize that the steps listed above to not include
any steps related to the creation
+or configuration of user accounts intended for end user connections. The user
accounts have not been created
+prior to the stage when the post-load script is executed.
+
+The post-load script is useful for:
+
+* Making changes to configuration files which require the IP address of the
compute node to be known
+* Registering the compute node with an external service such as for OS
activation or software licensing
+* Mounting external storage intended for system files or logs
+
+## Post-Reserve
+#### Script: /usr/local/vcl/vcl_post_reserve
+
+The post-reserve script is only executed when a user makes a reservation for
an image and acknowledges the
+reservation by clicking the Connect button. It is executed after the standard
*reserve* steps are performed
+via SSH by the management node's vcld process. These steps include:
+
+* Add user account(s) and set passwords if applicable
+* Grant access via SSH and other connect methods
+* For cluster reservations, the /etc/cluster_info file is created
+
+The post-reserve script is useful for:
+
+* Making changes to configuration files which require the username(s) to be
known
+* Starting services which should only run when the compute node is available
to an end user
+* Configuring the firewall to allow access to a particular service
+* Configuring interaction with other compute nodes assigned to a cluster by
parsing the cluster_info file and
+modifying configuration files with information about the other cluster nodes
+* Mounting external storage intended for user files
+
+## Post-Reservation
+####Script: /usr/local/vcl/vcl_post_reservation
+
+The post-reservation script is executed prior to a compute node being
reloaded. It does not matter if the
+compute node is reloaded with the same or a different image, nor does it
matter if the compute node was
+assigned to an end user reservation or simply is being reloaded via the
*Manage Computers* utility.
+
+The post-reservation script is useful for:
+
+* Stopping services
+* Unregistering the compute node from external services such as a license
server in order to free up a license
+for other users
+* Removing/unregistering the node from an external shared filesystem
\ No newline at end of file
