Oracle VM Template Developer’s Guide: Creating Pre-Built VMs for Rapid Software Deployment

Oracle White Paper—Oracle VM Template Developer’s Guide

An Oracle Technical White Paper

February 2009

Oracle VM Template Developer’s Guide:

Creating Pre-Built VMs for

Rapid Software Deployment

Oracle White Paper—Oracle VM Template Developer’s Guide

Introduction …………………………………………………………………………….. 1

Oracle VM Templates: Concept and Usage…………………………………. 2

Template Creation, Overview…………………………………………………. 2

What You Need to Know About Licenses ………………………………… 5

Prerequisites for Oracle VM Template Creation………………………… 6

Creating an Oracle VM Template……………………………………………….. 6

Step-by-Step: Template Creation……………………………………………….. 7

1. Decide On Your Template Specification ………………………………. 7

2. Using JeOS kit, Create the Initial Template …………………………. 8

3. Set-up the Template Development Environment …………………. 11

4. Configure the Virtual Machine for Product Installation ………….. 12

5. Install the Product Software into the VM …………………………….. 12

6. Identify Actions for Product Software Configuration at Install … 14

7. Define the Product Specific Reconfiguration Actions …………… 15

8. Define the Product Specific Cleanup Scripts ………………………. 16

9. Remove Proprietary Files from OS Disk Image & Replace

Parameter Values by Placeholder Strings ……………………………… 17

10. Package the Template …………………………………………………… 17

APPENDIX A…………………………………………………………………………. 20

APPENDIX B…………………………………………………………………………. 26

Oracle White Paper—Oracle VM Template Developer’s Guide

Introduction

An Oracle VM Template is a virtual machine (VM), or group of VMs, containing a full

software stack that is pre-installed, pre-configured, and ready to use. Simply download

and import a Template into Oracle VM, and then deploy the template as a VM in order to

use the pre-configured software. This eliminates the steps of installing, patching, and

configuring complex software.

Oracle VM Templates support both Oracle and non-Oracle applications, and can be built

by anyone including Oracle, ISVs, and third party solution providers. By using an

operating system like Oracle Enterprise Linux, developers can build their application as a

full stack virtual machine on an enterprise-class operating system that is freely

redistributable without any special agreement, and the template can be backed by

enterprise-class support.

This technical white paper is for those interested in knowing how to package applications

in a standard, pre-configured way as an Oracle VM Template. It’s a fast and reliable way

to deploy complex enterprise applications.

For information on the broader context of Oracle VM Templates, their benefits, and how

they are deployed, customized, and used from Oracle VM Manager, refer to the “Creating

and Using Oracle VM Templates: The Fastest Way to Deploy Any Enterprise Software”

white paper, and visit oracle.com/virtualization for more information about Oracle VM.

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Oracle VM Templates: Concept and Usage

The use of Oracle VM Templates for the deployment of applications in Oracle VM virtual

machines (VMs) eliminates the need for a user to install and configure the operating system and

applications. The templates can be simply downloaded and the virtual machine(s) can be brought

up either from the Oracle VM Manager browser interface or by using an xm command issued on

the Oracle VM server command line.

The OS and applications are configured at initial template boot time. The configuration can be

done based on certain default values and actions based on the user’s input. An example of a

default configuration is an Oracle Enterprise Linux (OEL) template using a DHCP assigned IP

address. No user input is required to configure the template. An example of boot time

reconfiguration is an OEL template with static IP. In this case, the, user would need to supply

values for the IP address, gateway, netmask, and DNS to the virtual machine before the boot

process can be completed.

If you wish the virtual machine to be configured with a static IP address and other non-default

settings, you need to develop the template configuration actions in the form of writing a

configuration script, which can process the user’s input and perform the corresponding

configuration steps upon initial boot of the VMs created from the template.

The remainder of this paper will focus on how to create and Oracle VM Template for any

software you wish to deploy as a complete, pre-built virtual machine.

Template Creation, Overview

An Oracle VM template consists of one or more binary files and a text file. The binary files are

the disk images taken from a fully configured and functional virtual machine. The text file is a

virtual machine configuration file. The files are shipped in one archive (or tar file). For example,

an archive (or tar file) of the Oracle 11g Database template contains 3 files in one directory:

oracle11g/system.img (disk image with OS)

/oracle11g.img (disk image with oracle software)

/vm.cfg (vm configuration file)

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The tar file contents can also be a multi-VM template set. For example, the Oracle Enterprise

Manager Grid Control template contains two virtual machines: a middle tier management server

(OMS) VM and a backend Oracle Database repository VM. Consequently, the template archive

consists of two directories, each containing 3 files:

db/system.img (disk image with OS)

/db.img (disk image with oracle DB software)

/vm.cfg (vm configuration file)

gc/system.img (disk image with OS)

/gc.img (disk image with oracle GC software)

/vm.cfg (vm configuration file)

Note: Packaging a template that consists of several virtual machines in a single archive simplifies

the download for the end user because there is less chance that an inconsistent or wrong

combination of VMs or files will be downloaded.

A template is a copy of a pre-installed virtual machine. To create this copy, one needs first to

create the virtual machine itself running the desired OS, and then install and configure the target

software. The next step is to implement a script to perform dynamic reconfiguration of the OS

and application at initial boot-time, if required.

The virtual machine with the desired OS can be created from scratch using Oracle Enterprise

Linux, or you can begin with an existing Oracle VM OS Template available from Oracle’s EDelivery

website. Oracle has made available for free download a “Just enough OS” or JeOS

edition of the Oracle Enterprise Linux 4 and 5 operating systems to facilitate building an OS

instance with a bare minimum number of packages needed for your template. This helps reduce

the disk footprint by up to 2GB or more per VM, and also improves security and reliability of the

virtual machine. Of course, you can customize and add packages to the JeOS edition package list

to completely tailor to the needs of the application. The JeOS edition download also includes a

script to help configure parameters such as disk sizes, etc.

Details on JeOS, including a complete description of the included modifyjeos script can be found

on the Oracle Open Source Software website at oss.oracle.com/el5/docs/modifyjeos.html

The dynamic reconfiguration boot time actions can be implemented in product specific scripts as

described later in this paper. The scripts are then installed in the template and can be set to

automatically run when the VM is first booted.

Note: Throughout the rest of this white paper, unless indicated otherwise, the term “product”

will be used to refer to any software product(s) included in the template in addition to the OS.

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Start VM from

Template

Reconfigure

Template?

Is template

product config

script available

Execute product

template

configuration script

Generate new

SSH host keys

and up2date UUID

Is product

image

available?

Mount Product

Image on /u01 Yes

Execute JeOS

reconfiguration

scripts: Obtain

network

configuration from

user at console

End

VM OS boots at

runlevel 3

End

No reconfiguration

required No Yes

Yes

Figure 1: The Virtual Machine Start-Up and Product Configuration Process. At the VM first boot, the VM OS (OEL) and application can be

configured with new IP address, hostname, and registered to the Unbreakable Linux Network for on-going support.

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What You Need to Know About Licenses

An Oracle VM Template can include any software and can be built by anyone. However, a

template developer or distributor should be aware of potential license implications.

Oracle VM Server and Oracle Enterprise Linux licenses are agreed upon at the time of download

from the E-Delivery website. The accepted End User License Agreement (EULA) is on the root

of the installation media (ISOs) downloaded and also included in the installed ovs-release and

enterprise-release packages (respectively). This covers Oracle VM Server and Oracle Enterprise

Linux only. Modifications or redistributions with other products thereafter may be or may not

be possible, and it is up to the individuals or organizations to consult the licensing terms for all

software included to ensure that use or distribution rights are not violated. Including software in

an Oracle VM Template does not reduce or eliminate any licensing obligations associated with

the included software.

Oracle VM Server and Oracle Enterprise Linux are free to download, use, and re-distribute. So a

template that contains only OEL (e.g. a default install of the OS) can be re-distributed without

any special agreement from Oracle.

Ease of Operations Maintenance

Since Oracle VM Templates do not require any proprietary directory structures or metadata,

there is no reason why the software included in the template cannot be completely compatible

with any utilities for patching and support provided by software vendors.

However, in order to support this compatibility, you may need to consider whether any

additional packages or software needs to be included in your template to support any required

vendor utilities used for maintenance of the template. For example, the template once deployed

should be able to support OS and product standard operating procedures going forward with

regards to:

• Patching

• Upgrade

• Configuration changes

• Monitoring

• Tech Support

For example, you should consider if it is likely that a monitoring agent, or agent used for

patching will need to be installed. You can consider either including these agents directly or just

plan to make sure the appropriate packages are included to allow future installation in the guest

VMs.

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Prerequisites for Oracle VM Template Creation

In order to get started, you will need access to the following items to develop a template. All of

the software referenced below can be downloaded free from eDelivery.oracle.com

• One physical server running Oracle VM Server software

• One Linux desktop or server running Oracle VM Manager

• Oracle Enterprise Linux JeOS software kit

• Root access to the dom0 on Oracle VM Server to package the template

For hardware requirements and other specifics on installing or using Oracle VM or Enterprise

Linux software, refer to the user documentation available at oracle.com/virtualization or

oracle.com/linux.

Creating an Oracle VM Template

There are 10 basic steps for creating an Oracle VM Template summarized below. Depending on

the type of software being included in the template, not every step will apply. Each step will be

described in detail, including an example based on the Oracle Enterprise Manager Agent

Template developed by Oracle. Overview of the basic template creation steps:

1. Decide on your spec for the template: operating system, product version, and product

configuration;

2. Using JeOS kit, create the initial template with OS disk image and placeholder disk

image for product installation;

3. Setup a development environment;

4. Configure the virtual machine for the product installation;

5. Install the product software (e.g. Oracle database, Enterprise Manager Agent, etc.);

6. Identify the product configuration actions normally performed product installation that

will need to be performed by a template configuration script (e.g. system files modified,

product configuration files that refer to used-at-install hostname, IP address);

7. Develop a script for the product specific reconfiguration actions (e.g. in product

configuration files, replacement of used-at-install IP address by actual IP address assigned to

the virtual machine at deployment);

8. Develop the product specific cleanup scripts;

9. Remove the proprietary files from OS disk image and replace the relevant real parameter

values by placeholders;

10. Package and archive the template.

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Step-by-Step: Template Creation

1. Decide On Your Template Specification

The first step is to specify the technical requirements for the template:

• OS version to include

• Guest type: paravirtualized (PVM) or fully virtualized (also known as “hardware virtualized” or

“HVM”). Generally stated, PVMs are higher performance and more scalable and thus are generally

preferable. Consult Oracle VM user documentation and white papers for more discussion on

PVMs vs. HVMs

• Version of product(s) to install

• Product configuration

• Product install directory

• Product install partition size

• Number of virtual CPUs to be configured when the guest VM is created. Note that this value

can be edited later and even changed from the Oracle VM Manager GUI.

• Size of virtual memory. Note that, in Oracle VM, as with any virtualization product using the

Xen hypervisor component, the amount of memory consumed by all the VMs running on a

physical server at any one time cannot exceed the amount of physical memory in the server. This

may be a consideration if you plan on running multiple VMs on the same physical machine.

• Swap size: Depends on the application. For Linux operating systems, 512B-1024GB is usually

sufficient but more may be ideal for your application. For example, for Oracle Database, 2GB is

recommended.

• Free size of root partition desired after OS install

• Name for your product disk images

• Mount point for the product disk image(s)

• Template name (default name for the archive and virtual machine(s)). Keep in mind that

templates containing multiple VMs will create a separate directory based on the VM name for each

VM. To avoid later confusion or conflicts when you have many templates deployed in the same

Oracle VM instance, it is recommended that you develop a naming convention that will not only

contain the name of the individual VM but also the name of the template that it is associated with.

For example, if you have multiple templates that contain a database VM, do not name each VM

simply as “database” because this will create a directory naming conflict but also create confusion

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later as to which overall template a given “database” belongs-to. Also keep in mind versioning as

you are likely to update the template over time with patched or updated software or settings.

• Dependencies, overall topology, or other things specific to the products you are including.

Note: Although Oracle developed templates generally include two virtual disk images, it is

technically optional to create a second disk for the application install and it may or may not be

required for a given template. But, often two disk images may be needed to separate products

with different license terms and conditions, e.g. to separate software with open licenses such as

GPL from software or files that have a proprietary license. Consult the software license authority

with any questions regarding licensing requirements.

Step 1 Example: Oracle Enterprise Manager Agent Template – Template Specification

In this example of an Oracle Enterprise Manager Agent template, the template specification is as

follows:

• OS version: Enterprise Linux 5 Update 2 for x86 platform

• Guest type: Paravirtulized (PVM)

• Product Version: EM Agent 10.2.0.4 for Linux x86

• Product configuration: standard install

• Product install directory: /u01.

• Product install disk size: 5 GB

• Number of virtual CPU: 1

• Size of virtual memory: 1GB

• Swap size: 2GB

• Free size of root partition after OS install: 2GB

• Name for your product disk images: Emagent.img

• Mount point for the product disk image: /u01

• Template name: OVM_EL5U2_X86_EMAGENT_PVM.

2. Using JeOS kit, Create the Initial Template

Oracle recommends using the Oracle Enterprise Linux JeOS kit for creating a tailored for your

product OS image and product disk.

oracle.com/technology/software/products/virtualization/vm_jeos.html

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Download and install JeOS rpm to a system running OEL 5 Update 2 or later. It can be either a

bare metal system or a virtual machine. The documentation, which is part of the rpm, is a

comprehensive guide on how to develop with JeOS.

Tips:

-The JeOS edition of Enterprise Linux only includes English language support by default. If your

template needs to support additional languages, these packages should be added to your OS

build.

-If you have rpm-based software products you wish to include and can configure access to the

rpm repository for that software, you may provide those packages as input to modifyjeos

command. If the product(s) you wish to add are not rpm based, and need to run their own

installer, you can do so by running the installer in the VM before completion of your template

packaging as described later in this paper.

Step 2 Example: Oracle Enterprise Manager Agent Template – Initial Template Creation with OEL JeOS

As a root user, install JeOS kit on the virtual machine running OEL5.2:

ovm-modify-jeos-1.1.0-2.el5.noarch.rpm

ovm-el5u2-xvm-jeos-1.1.0-1.el5.i386.rpm

Create the working directory to be used for JeOS output files and enter

this directory:

# mkdir /<any_path>/emagent_work

# cd /<any_path>/emagent_work

To create the template, we need to know the disk size(s), number of

virtual CPUs and memory size. This information should have been included

as a part of the specification described in Step 1 above.

Identify the additional packages required for the product. Get these

packages using modifyjeos and specify either a DVD ISO mount point or a

YUM repository on the network as a repository location. It should be

local ISO (DVD) or YUM repository accessible via network. Refer to JeOS

documentation for more details.

We will use an YUM repository as the source for packages in this example:

http://public-yum.oracle.com/repo/EnterpriseLinux/EL5/2/base/i386

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The addpkg.lst file used as input by JeOS contains a list of additional

packages to be added to the standard, base JeOS image. For an EMagent

install, create ‘addpkg.lst’ with the following lines (packages):

* oracle-validated

Note that this is a very special and helpful rpm if your template will

include the Oracle Database or other software that depends on some of the

Database libraries, as is the case with the EM Agent. Basically you can

think of this as a kind of “master rpm” that contains references to all

the dependencies / rpms that you need on top of the JeOS base to support

the Database. By specifying this package alone, it will pull-in and

install all the other packages recommended and required by Oracle for the

Database, eliminating the need to manually identify each individual

Database package required. Named after, and derived from Validated

Configurations program, oracle-validated also creates an oracle OS user

and an oinstall and dba group. Kernel parameters are also set properly,

ensuring that the Oracle Universal Installer will proceed without

complaints.

* nc – required, used in template reconfiguration script

* unzip – optional but recommended, may be used to unzip the Agent

software source

* wget – optional but recommended, may be used to download the Agent

software.

Next, run the modifyjoes command to add the packages and generate the

.img and vm.cfg files:

# modifyjeos -i EL52_i386_PVM_jeos \

-n OVM_EL5U2_X86_EMAGENT_PVM \

-mem 1024 -cpu 1 \

-r http:// public-yum.oracle.com

repo/EnterpriseLinux/EL5/2/base/i386 \

-p addpkg.lst \

-S 2048 -I 6096 -R 2048 \

-P Emagent.img 5120 /u01 \

-conf /u01/emagent-reconfig.sh \

-cln /u01/emagent-cleanup.sh

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u01/emagent-reconfig.sh referenced above is the name of reconfiguration

script we’ll develop later in Step 7.

/u01/emagent-cleanup.sh referenced above is the name of cleanup script

we’ll develop later in Step 8.

The following files are then produced in the current directory:

·System.img: This is the OS system image file

·Emagent.img: This is the image file for the EM agent

·vm.cfg: This is the virtual machine configuration file describing the

parameters needed to create the guest VM.

A partition with ext3 file system is created on Emagent.img and the

partition will be mounted on /u01.

Copy these three files to the directory reachable via http or ftp, for

example to /var/www/html/emagent_templ.

Note: For a complete description of all the modifyjeos options, refer to

the README file hosted at http://oss.oracle.com/el5/docs/modifyjeos.html

3. Set-up the Template Development Environment

Install the Oracle VM Server and Oracle VM Manager software if you have not installed them

already.

location via the wizard initiated from the ‘Import’ button on the Virtual Machines page. Start the

virtual machine. Refer to Oracle VM Manager User’s Guide for complete details on importing

and starting VMs in Oracle VM Manager.

Once the virtual machine has powered-on, you can login to the virtual machine as user ‘root‘ via

Oracle VM Manager’s VNC ‘Console’ button using password ‘ovsroot’‘.

Step 3 Example: Oracle Enterprise Manager Agent Template – Set-up Development Environment

In our example, we have Oracle VM server installed already, and have

imported the initial VM (the disk images and vm.cfg created in step 2)

into Oracle VM Manager. We now start the virtual machine using Oracle VM

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Manager and then open the virtual machine console using the ‘Console’

button on the ‘Virtual Machines’ page.

You’ll be prompted to choose DHCP configuration or specify the IP

address, gateway, netmask, and DNS to configure the virtual machine

network. Choose the option which works better for you. It will not have

an effect on the template eventually created.

Answer the interview questions, and login to running virtual machine as

user ‘root’ using password ‘ovsroot’.

4. Configure the Virtual Machine for Product Installation

You may need to do additional OS configuration for the included product software. This may

include additional OS parameter settings and disk configuration but is completely dependent on

the specifics of the products that are included.

JeOS already configures swap and the disk for product installation for you. By default, the ext3

filesystem is used for the product disk format. Unless you want to change the filesystem format

from ext3 or the disk size, you do not need change anything.

Next, if you need a raw partition, additional configuration will be needed. For example, if you

need a partition for the datafiles located on Oracle ASM (Automatic Storage Management)

devices, you could create a second “product disk” using the modifyjeos script. But instead of

using it as a filesystem, un-mount that device and use the partition (e.g. /dev/xvdc1) for the

ASM device.

If you need to modify the OS parameters manually, you may need to edit OS configuration files.

For example, to set the kernel parameters per product requirement, you may need to edit

/etc/sysctl.conf as root.

Step 4 Example: Oracle Enterprise Manager Agent Template – Configuring Source Virtual Machine

We used JeOS to install the required dependant packages, and configure

the second disk. The oracle-validated.rpm created all the required user

accounts and set all the required OS parameters.

Refer to Oracle Database Installation Guide for information about oraclevalidated.

rpm.

5. Install the Product Software into the VM

Install the software into the VM(s) and perform the required configuration (sizing, data

population). As previously mentioned, if your software installation is completely rpm-based, you

could add it to the list of packages to be installed in the image created by JeOS. But if your

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product installation is not rpm-based, and you need to run your installer, you would run it as a

part of this step.

For the product install, use the disk mounted at the mount point specified during the spec phase

(Step 1). This disk may or may not be formatted with the file system depending on how you

created the template.

Step 5 Example: Oracle Enterprise Manager Agent Template – Install Product Software

We downloaded agent software from the Oracle Technology Network (OTN) and

did an install using silent installation mode (refer to the Oracle

Enterprise Manager Installation Guide).

1)On the product image disk mounted at /u01, create a directory owned by

user ‘oracle’ and group ‘dba’

# mkdir /u01/app

# chown oracle:dba /u01/app

2) Check and configure the hostname, both in file /etc/hosts, and by

using command “hostname”, as the agent installer will check the local

hostname

3)Extract the agent install media from downloaded zip file

Unzip it in <UNZIP_DIR> directory

4) Modify <UNZIP_DIR>/response/additional_agent.rsp, set

BASEDIR=u01/app/oracle/product

sl_OMSConnectInfo={“dummy”, “9999”}

These ‘dummy’ host name and ‘dummy’ port allows to install emagent

without registering to OMS server. This is convenient if you do not have

OMS server installed in your environment. You can specify the values for

real OMS hostname and port if you wish. In this example, we assume that

there is no OMS server available at the template development time.

5) Invoke OUI in silent mode:

# su – oracle

# <UNZIP_DIR>/linux/agent/runInstaller –silent –force -noConfig –

responseFile <UNZIP_DIR>/linux/response/additional_agent.rsp

In the above syntax, -force noConfig is required if you run installer

with ‘dummy’ OMS server.

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6) as root user, run post install scripts

/u01/app/oraInventory/orainstRoot.sh

/u01/app/oracle/product/agent10g/root.sh

6. Identify Actions for Product Software Configuration at Install

Next you need to analyze all the product configuration steps that were required to support

network, storage, or user specific configuration. Specifically, you need to note any items that

would likely need to be reconfigured when the virtual machine is deployed in a new environment

since the networking or storage or hostnames, etc. might be different. Reconfiguration of these

items will need to be provided as a part of your OS or product reconfiguration scripts as

described in section 7 below. Those could include any of the following:

• Files with modified content

• File and directory names modified

• Data entries in the database

• Dependencies on other existing environments

• Other items specific to the products installed

Step 6 Example: Oracle Enterprise Manager Agent Template – Identify the Reconfiguration Actions

In the case of the Oracle EM Agent, each agent instance has to register

with the OMS (Oracle Management Service) of Enterprise Manager.

Normal EM Agent installation also requires the following data for each

new instance:

·Management Service hostname

·Management Service IP address (if hostname cannot be resolved)

·Management Service Port

·Agent Registration password

Those parameter values need to be obtained from the user at initial

template boot

The configuration file for the EM agent is:

·$AGENT_HOME/sysman/config/emd.properties

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OMS port and OMS hostname values are embedded into URLs for OMS Wallet

Source and OMS repository parameters. Those values need to be replaced at

the template boot to reflect the deployment setting.

It may be helpful to create a table describing the parameter names, their

values, and where they are stored such as is shown below to help keep

track of everything that will need to be addressed in the script(s):

Value Stored in Where / When to

configure

OMS hostname emdWalletSrcUrl parameter emd.properties file

OMS port emdWalletSrcUrl parameter emd.properties file

OMS hostname REPOSITORY_URL parameter emd.properties file

OMS port REPOSITORY_URL parameter emd.properties file

Agent password OMS Database At agent registration

7. Define the Product Specific Reconfiguration Actions

Now that you have analyzed and collected the list of parameters that would need to be set

uniquely for each VM instance created from the template, you need to develop the scripts to

gather the information and set the values. The script should perform the following tasks:

• Collect from the user the values for configurable parameters

• Perform the software application reconfiguration

• Start the software application if applicable

Step 7 Example: Oracle Enterprise Manager Agent Template – Develop The Product Specific

Configuration Scripts

For this EM agent example, the script is called ’emagent-reconfig.sh’ and

should be copied into /u01/. We used this name emagent-reconfig.sh when

we ran the modifyjeos command above in Step 2.

Refer to Appendix A at the end of this paper for the full source code for

the template reconfiguration script for this example.

The script is executed at the first boot of the VM created from the

template. The actions performed by the script are based on data from

Step 6, and consist of three logical parts:

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1. Interactively collect the user’s input using a VNC session brought up

at first boot. Again, the VM console can be accessed by selecting the VM

in Oracle VM Manager and clicking on the ‘Console’ button in the UI.

2. Replace the placeholder strings by real data for parameters defined

in the example in Step 6:

sed -i “/^emdWalletSrcUrl/s|%OMS_HOST%|$OMS_HOST|”

$AGENT_HOME/sysman/config/emd.properties

sed -i “/^emdWalletSrcUrl/s|%OMS_PORT%|$OMS_PORT|”

$AGENT_HOME/sysman/config/emd.properties

sed -i “/^REPOSITORY_URL/s|%OMS_HOST%|$OMS_HOST|”

$AGENT_HOME/sysman/config/emd.properties

sed -i “/^REPOSITORY_URL/s|%OMS_PORT%|$OMS_PORT|”

$AGENT_HOME/sysman/config/emd.properties

sed -i “/^EMD_URL/s|%HOSTNAME%|$(hostname)|”

$AGENT_HOME/sysman/config/emd.properties

Note, that to make this approach work, before you archive the template, you need to substitute the

development VM parameter values in configuration file by placeholders like ‘%OMS_HOST’. This

will be done in steps 8 and 9.

3. Start the EM agent and register it to OMS

After you finish the development and testing of the script, copy it to

/u01.

8. Define the Product Specific Cleanup Scripts

Based on analysis of all the product installation and configuration steps, determine the cleanup

tasks that need to be done. These may include any of the following:

• Deleting product installation and other log files

• Deleting runlevel startup scripts

• Replacing the product parameter values by placeholders in the product configuration scripts

Then, you need to develop the scripts to perform these tasks.

Step 8 Example: Oracle Enterprise Manager Agent Template – Product Specific Cleanup Scripts

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For this EM agent example, the cleanup script is called ’emagentcleanup.

sh’. We introduced this script name, emagent-cleanup.sh, when we

ran the modifyjeos script in Step 2.

Develop the script, and copy it to /u01 directory.

Refer to Appendix B at the end of this paper for the source code for the

template clean up script for this example.

9. Remove Proprietary Files from OS Disk Image & Replace

Parameter Values by Placeholder Strings

If the product is up and running, shut it down cleanly.

Run the JeOS cleanup script

# oraclevm-template –cleanup

The JeOS cleanup script invokes the product specific script (emagent-cleanup.sh in our example).

Hence, all product specific cleanup actions will be done. For example, the used-at-product-install

parameter values will be replaced by placeholders in the product configuration files.

The JeOS script cleans up the OS log files in /var/log, removes the systemid from up2date

configuration file, cleans up the yum caches, DHCP client caches, the root user’s ssh

configuration file and bash history files, removes etc/resolv.conf, resets /etc/hostnames to

default, resets network configuration to DHCP, and, finally, shuts down network service.

Enable ‘oraclevm-template’ service

# oraclevm-template -enable

This will make the template ready for the first boot, i.e. will set the sysconfig flag

/RUN_TEMPLATE_CONF/ to /YES/.

Step 9 Example: Oracle Enterprise Manager Agent Template – Clean Up The Disk Image

Run

# oraclevm-template –cleanup

# oraclevm-template –enable

10. Package the Template

• Shutdown the virtual machine

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• Copy the virtual machine directory from Oracle VM Server back to the machine where

JeOS kit is installed

• Replace the modified vm.cfg file by the original vm.cfg created by JeOS

• Zero out the free space in the image files

• Archive the template

Step 10 Example: Oracle Enterprise Manager Agent Template – Package the Template

To package the template, you need a root access to Oracle VM server

Shutdown the virtual machine via OVM Manager UI.

Do remote copy of the entire <VM ID>emagent directory content including

vm.cfg, vm.cfg.orig, System.img and Emagent.img back to environment where

JeOS kit is installed. In our example that was OEL 5.2 virtual machine.

From any directory in this virtual, issue

# scp -r root@<Oracle VM Server>:/OVS/running_pool/<VM ID>_emagent

OVM_EL5U2_X86_EMAGENT_PVM

Change the working directory to OVM_EL5U2_X86_EMAGENT_PVM

#cd OVM_EL5U2_X86_EMAGENT_PVM

Replace the vm.cfg file generated by OVM manager by the original vm.cfg

file created by JeOS. The vm.cfg generated by JeOS is the more generic

template vm.cfg file and thus does not contain the MAC address that is

specific to the VM you created for development purposes.

# cp /var/www/html/emagent_templ/vm.cfg vm.cfg

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Zero out image file content:

#modifyjeos –f System.img –zero-out-all

This command will automatically mount all other images that are part of a

template

Convert image files to sparse image format

#cp –sparse=always System.img System.img.sparse

#mv System.img.sparse System.img

#cp –-sparse=always Emagent.img Emagent.img.sparse

#mv Emagent.img.sparse Emagent.img

#cd ..

Archive the template

# tar -czvSf OVM_EL5U2_X86_EMAGENT_PVM.tgz OVM_EL5U2_X86_EMAGENT_PVM

Conclusion

Packaging software as Oracle VM Templates simplifies the product deployment process, saves

time, and improves the end-user’s experience. With Oracle VM Templates, developers can

deliver best practices for software deployment while not restricting users to rigid configurations.

For a broader discussion of Oracle VM Templates, refer to the “Creating and Using Oracle VM

Templates: The Fastest Way to Deploy Any Enterprise Software” white paper.

Also, visit oracle.com/virtualization for more information about Oracle VM.

Oracle White Paper—Oracle VM Template Developer’s Guide

APPENDIX A

Source Code for Agent Template Reconfiguration Script, /u01/emagent-reconfig.sh

#!/bin/bash

case “$ORACLE_TRACE” in

T) set -x ;;

*) ;;

esac

# oms_connection function interactively collects user’s input for

# OMS hostname, ip address, password, and port numbers

oms_connection () {

local oms_hostname

local oms_ip

local oms_host

local oms_port

# ask for oms connection information.

echo

echo “Provide Management Service hostname”

while true; do

# oms hostname

while true; do

echo -n “Enter OMS hostname: ”

read oms_hostname

if [ -z $oms_hostname ]; then

continue

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break

done

# if can not resolve the hostname, then request IP address

if ! ping -c 3 $oms_hostname >/dev/null 2>&1; then

echo “*Can not resolve hostname $oms_hostname.”

while true; do

echo -n “Enter OMS IP address: ”

read oms_ip

if [ -z $oms_ip ]; then

continue

break

done

if [ ! -z $oms_ip ]; then

oms_host=$oms_ip

else

oms_host=$oms_hostname

# oms port

echo -n “Enter OMS port: [4889] ”

read oms_port

if [ -z “$oms_port” ]; then

oms_port=4889

# test connection

if ! nc -w 3 -z $oms_host $oms_port >/dev/null; then

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echo “*Can NOT connect to $oms_host:$oms_port, please enter OMS information again.”

oms_ip=

continue

else

OMS_HOST=$oms_hostname

OMS_PORT=$oms_port

if [ ! -z “$oms_ip” ]; then

/bin/cp -f /etc/hosts /etc/hosts.orabak$$

sed -i “/^$oms_ip/d” /etc/hosts

echo “$oms_ip $OMS_HOST ${OMS_HOST%%.*}” >> /etc/hosts

break

done

# enter password

echo

echo “Provide the Agent Registration password so that the Management Agent can

communicate with Secure Management Service.”

while true; do

echo -n “Enter Agent Registration Password: ”

stty -echo

read secure_passwd

stty echo

echo

if [ -z $secure_passwd ]; then

continue

break

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done

SECURE_PASSWD=$secure_passwd

}

# source functions that are part of standard JeOS template

. /usr/lib/oraclevm-template/functions

# ovm_configure_network function is part of JeOS function library

# this function interactively collects user’s input for the

# virtual machine network configuration: IP address, hostname,

# gateway,netmask, DNS

ovm_configure_network

# Reconfigure agent

echo

echo “Reconfiguring Agent…”

# Parameters to be reconfigured

OMS_HOST=

OMS_PORT=

SECURE_PASSWD=

# Get parameter values from user input

oms_connection

AGENT_HOME=/u01/app/oracle/product/agent10g

# replace the placeholder values by the actual OMS hostname, port and virtual machine

hostname in emd.properties

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sed -i “/^emdWalletSrcUrl/s|%OMS_HOST%|$OMS_HOST|”

$AGENT_HOME/sysman/config/emd.properties

sed -i “/^emdWalletSrcUrl/s|%OMS_PORT%|$OMS_PORT|”

$AGENT_HOME/sysman/config/emd.properties

sed -i “/^REPOSITORY_URL/s|%OMS_HOST%|$OMS_HOST|”

$AGENT_HOME/sysman/config/emd.properties

sed -i “/^REPOSITORY_URL/s|%OMS_PORT%|$OMS_PORT|”

$AGENT_HOME/sysman/config/emd.properties

sed -i “/^EMD_URL/s|%HOSTNAME%|$(hostname)|”

$AGENT_HOME/sysman/config/emd.properties

# Reconfiguration of Oracle EM agent is done

# Open ports for Oracle EM Agent and ssh services

system-config-securitylevel-tui –quiet \

–port=3872 \

–port=ssh

# reconfigure and rediscover targets

echo

su oracle -c “$AGENT_HOME/bin/agentca -f -d -t”

# secure Oracle EM agent

echo

echo “Securing Agent…”

su oracle -c “$AGENT_HOME/bin/emctl secure agent $SECURE_PASSWD”

# Start Oracle EM agent

echo

echo “Starting Oracle EM Agent…”

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/etc/init.d/gcstartup start

# create startup script at runlevel 3 5

ln -sf /etc/rc.d/init.d/gcstartup /etc/rc.d/rc3.d/S99gcstartup

ln -sf /etc/rc.d/init.d/gcstartup /etc/rc.d/rc5.d/S99gcstartup

# set env variable for user ‘oracle’

cat >> /home/oracle/.bash_profile <<-EOF

# set environment variables

AGENT_HOME=$AGENT_HOME

ORACLE_HOME=\$AGENT_HOME

JAVA_HOME=\$ORACLE_HOME/jdk

PATH=\$ORACLE_HOME/bin:\$ORACLE_HOME/OPatch:\$PATH

EM_SECURE_VERBOSE=1

export ORACLE_HOME AGENT_HOME JAVA_HOME EM_SECURE_VERBOSE PATH

alias cdo=’cd \$ORACLE_HOME’

EOF

echo

echo “Reconfiguration of OEL5.2 and EM Agent 10.2.0.4 completed”

press_anykey

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APPENDIX B

Source Code for Agent Template Reconfiguration Script, /u01/emagent-cleanup.sh

#!/bin/bash

AGENT_HOME=/u01/app/oracle/product/agent10g/

# substitute the parameter values by place holders

sed -i \

-e

‘/^REPOSITORY_URL=/s|=.*|=http://%OMS_HOST%:%OMS_PORT%/em/upload|’ \

-e

‘/^emdWalletSrcUrl=/s|=.*|=http://%OMS_HOST%:%OMS_PORT%/em/wallets/emd|’ \

-e ‘/^EMD_URL/s|=.*|=https://%HOSTNAME%:3872/emd/main/|’ \

$AGENT_HOME/sysman/config/emd.properties

# remove log files

rm -f $AGENT_HOME/sysman/log/*

# remove agent’s targets data

rm -f $AGENT_HOME/sysman/emd/upload/*

rm -rf $AGENT_HOME/sysman/emd/state/*

rm -f $AGENT_HOME/sysman/emd/lastupld.xml

# remove the runlevel startup script

rm -f /etc/rc.d/rc3.d/S99gcstartup

rm -f /etc/rc.d/rc5.d/S99gcstartup

Oracle VM Template Developer’s Guide

February 2009

Author: Tatyana Bagerman

Contributing Authors: Wiekus Beukes, Frank

Deng, Van Okamura

Oracle Corporation

World Headquarters

500 Oracle Parkway

Redwood Shores, CA 94065

U.S.A.

Worldwide Inquiries:

Phone: +1.650.506.7000

Fax: +1.650.506.7200

oracle.com

the contents hereof are subject to change without notice. This document is not warranted to be error-free, nor subject to any other

warranties or conditions, whether expressed orally or implied in law, including implied warranties and conditions of merchantability or

fitness for a particular purpose. We specifically disclaim any liability with respect to this document and no contractual obligations are

formed either directly or indirectly by this document. This document may not be reproduced or transmitted in any form or by any

means, electronic or mechanical, for any purpose, without our prior written permission.

Oracle is a registered trademark of Oracle Corporation and/or its affiliates. Other names may be trademarks of their respective

owners.

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