Frequently Asked Questions on Linux Provisioning

What is PXE (Pre-boot Execution Environment)?

The Pre-boot Execution Environment (PXE, aka Pre-Execution Environment) is an environment to bootstrap computers using a network interface card independently of available data storage devices (like hard disks) or installed operating systems. See: Understanding PXE Booting and Kickstart Technology for more information.

Can my boot server reside on a subnet other than the one on which the bare metal boxes will be added?

Yes. But it is a recommended best practice to have boot server in the same subnet on which the bare metal boxes will be added. If the network is subdivided into multiple virtual networks, and there is a separate DHCP/PXE boot server in each network, the Assignment must specify the boot server on the same network as the designated hardware server.

If one wants to use a boot server in a remote subnet then one of the following should be done:

-- Router should be configured to forward DHCP traffic to a DHCP server on a remote subnet. This traffic is broadcast traffic and routers do not normally forward broadcast traffic unless configured to do so. A network router can be a hardware-based router, such as those manufactured by the Cisco Corporation or software-based such as Microsoft's Routing and Remote Access Services (RRAS). In either case, you need to configure the router to relay DHCP traffic to designated DHCP servers.

-- If routers cannot be used for DHCP/BOOTP relay, set up a DHCP/BOOTP relay agent on one machine in each subnet. The DHCP/BOOTP relay agent relays DHCP and BOOTP message traffic between the DHCP-enabled clients on the local network and a remote DHCP server located on another physical network by using the IP address of the remote DHCP server.

Why is Agent rpm staged on the Stage server?

Agent rpm is used for installing the agent on the target machine after booting over the network using PXE. With operating system provisioning, agent bits are also pushed on the machine from the staging location specified in the Advanced Properties.

Can I use the Agent rpm for installing Agent on Stage and Boot Server?

This is true only if the operating system of the Stage or Boot Server machine is RedHat Linux 4.0, 3.1 or 3.0 or Oracle Linux 4.0 or later.

Can the yum repository be accessed by any protocol other than HTTP?

Though the rpm repository can be exposed via file:// or ftp:// as well, the recommended method is to expose it via http://. The latter is faster and more secure.

What is the significance of the Status of a directive? How can one change it?

Look at the following table to know the possible Status values and what they signify.

Table B-1 Status Values

Status	Description
Incomplete	This Status signifies that some step was not completed during the directive creation, for example uploading the actual script for the directive, or a user saved the directive while creating it and still some steps need to be performed to make complete the directive creation.
Ready	his signifies that the directive creation was successful and the directive is now ready to be used along with any component/image.
Active	A user can manually change the status of a Ready directive to Active to signify that it is ready for provisioning. Clicking Activate changes the Status to Active.

What is a Maturity Level of a directive? How can one change it?

See Table B-2 to know the possible Status values and what they signify:

Table B-2 Maturity Levels

Maturity Level	Maturity Level Description
Untested	This signifies that the directive has not been tested and is the default maturity level that is assigned to the directive when it is created.
Beta	A directive can be manually promoted to Beta using the Promote button after testing the directive.
Production	A directive can be manually promoted to Production using the Promote button after a user is satisfied that the directive can be used for actual provisioning on production systems.

Can a same component be used in multiple deployments?

Yes. Components are reusable and a given component can be a part of multiple deployments at the same time.

Do I need to edit scheduled deployments associated with a component, if the component is edited?

Yes.

For creating the Linux OS component does the Reference Machine need to have a management agent running on it?

Yes. Reference Machine has to be one of the managed targets of the Enterprise Manager.

What is the significance of the Status of a component? How can one change it?

Status of a component is similar to that of a directive. Refer to What is the significance of the Status of a directive? How can one change it?.

What is a Maturity Level of a component? How can one change it?

Maturity Level of a component is similar to that of a directive. Refer to What is a Maturity Level of a directive? How can one change it?.