source/templates.rst

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Working with Templates
======================

A template is a reusable configuration for virtual machines. When users
launch VMs, they can choose from a list of templates in CloudStack.

Specifically, a template is a virtual disk image that includes one of a
variety of operating systems, optional additional software such as
office applications, and settings such as access control to determine
who can use the template. Each template is associated with a particular
type of hypervisor, which is specified when the template is added to
CloudStack.

CloudStack ships with a default template. In order to present more
choices to users, CloudStack administrators and users can create
templates and add them to CloudStack.


Creating Templates: Overview
----------------------------

CloudStack ships with a default template for the CentOS operating
system. There are a variety of ways to add more templates.
Administrators and end users can add templates. The typical sequence of
events is:

#. Launch a VM instance that has the operating system you want. Make any
   other desired configuration changes to the VM.

#. Stop the VM.

#. Convert the volume into a template.

There are other ways to add templates to CloudStack. For example, you
can take a snapshot of the VM's volume and create a template from the
snapshot, or import a VHD from another system into CloudStack.

The various techniques for creating templates are described in the next
few sections.


Requirements for Templates
--------------------------

-  For XenServer, install PV drivers / Xen tools on each template that
   you create. This will enable live migration and clean guest shutdown.

-  For vSphere, install VMware Tools on each template that you create.
   This will enable console view to work properly.


Best Practices for Templates
----------------------------

If you plan to use large templates (100 GB or larger), be sure you have
a 10-gigabit network to support the large templates. A slower network
can lead to timeouts and other errors when large templates are used.


The Default Template
--------------------

CloudStack includes a CentOS template. This template is downloaded by
the Secondary Storage VM after the primary and secondary storage are
configured. You can use this template in your production deployment or
you can delete it and use custom templates.

The root password for the default template is "password".

A default template is provided for each of XenServer, KVM, and vSphere.
The templates that are downloaded depend on the hypervisor type that is
available in your cloud. Each template is approximately 2.5 GB physical
size.

The default template includes the standard iptables rules, which will
block most access to the template excluding ssh.

.. code:: bash

   # iptables --list
   Chain INPUT (policy ACCEPT)
   target     prot opt source               destination
   RH-Firewall-1-INPUT  all  --  anywhere             anywhere

   Chain FORWARD (policy ACCEPT)
   target     prot opt source               destination
   RH-Firewall-1-INPUT  all  --  anywhere             anywhere

   Chain OUTPUT (policy ACCEPT)
   target     prot opt source               destination

   Chain RH-Firewall-1-INPUT (2 references)
   target     prot opt source               destination
   ACCEPT     all  --  anywhere             anywhere
   ACCEPT     icmp --  anywhere        anywhere       icmp any
   ACCEPT     esp  --  anywhere        anywhere
   ACCEPT     ah   --  anywhere        anywhere
   ACCEPT     udp  --  anywhere        224.0.0.251    udp dpt:mdns
   ACCEPT     udp  --  anywhere        anywhere       udp dpt:ipp
   ACCEPT     tcp  --  anywhere        anywhere       tcp dpt:ipp
   ACCEPT     all  --  anywhere        anywhere       state RELATED,ESTABLISHED
   ACCEPT     tcp  --  anywhere        anywhere       state NEW tcp dpt:ssh
   REJECT     all  --  anywhere        anywhere       reject-with icmp-host-


Private and Public Templates
----------------------------

When a user creates a template, it can be designated private or public.

Private templates are only available to the user who created them. By
default, an uploaded template is private.

When a user marks a template as “public,” the template becomes available
to all users in all accounts in the user's domain, as well as users in
any other domains that have access to the Zone where the template is
stored. This depends on whether the Zone, in turn, was defined as
private or public. A private Zone is assigned to a single domain, and a
public Zone is accessible to any domain. If a public template is created
in a private Zone, it is available only to users in the domain assigned
to that Zone. If a public template is created in a public Zone, it is
available to all users in all domains.


Creating a Template from an Existing Virtual Machine
----------------------------------------------------

Once you have at least one VM set up in the way you want, you can use it
as the prototype for other VMs.

#. Create and start a virtual machine using any of the techniques given
   in `“Creating VMs” <virtual_machines.html#creating-vms>`_.

#. Make any desired configuration changes on the running VM, then click
   Stop.

#. Wait for the VM to stop. When the status shows Stopped, go to the
   next step.

#. Click Create Template and provide the following:

   -  **Name and Display Text**. These will be shown in the UI, so
      choose something descriptive.

   -  **OS Type**. This helps CloudStack and the hypervisor perform
      certain operations and make assumptions that improve the
      performance of the guest. Select one of the following.

      -  If the operating system of the stopped VM is listed, choose it.

      -  If the OS type of the stopped VM is not listed, choose Other.

      -  If you want to boot from this template in PV mode, choose Other
         PV (32-bit) or Other PV (64-bit). This choice is available only
         for XenServere:

         .. note:: 
            Generally you should not choose an older version of the OS 
            than the version in the image. For example, choosing CentOS 
            5.4 to support a CentOS 6.2 image will in general not work. 
            In those cases you should choose Other.

   -  **Public**. Choose Yes to make this template accessible to all
      users of this CloudStack installation. The template will appear in
      the Community Templates list. See `“Private and
      Public Templates” <#private-and-public-templates>`_.

   -  **Password Enabled**. Choose Yes if your template has the
      CloudStack password change script installed. See 
      :ref:`adding-password-management-to-templates`.

#. Click Add.

The new template will be visible in the Templates section when the
template creation process has been completed. The template is then
available when creating a new VM.


Creating a Template from a Snapshot
-----------------------------------

If you do not want to stop the VM in order to use the Create Template
menu item (as described in `“Creating a Template from an Existing 
Virtual Machine” <#creating-a-template-from-an-existing-virtual-machine>`_), 
you can create a template directly from any snapshot through the 
CloudStack UI.


Uploading Templates
-------------------


vSphere Templates and ISOs
--------------------------

If you are uploading a template that was created using vSphere Client,
be sure the OVA file does not contain an ISO. If it does, the deployment
of VMs from the template will fail.

Templates are uploaded based on a URL. HTTP is the supported access
protocol. Templates are frequently large files. You can optionally gzip
them to decrease upload times.

To upload a template:

#. In the left navigation bar, click Templates.

#. Click Register Template.

#. Provide the following:

   -  **Name and Description**. These will be shown in the UI, so choose
      something descriptive.

   -  **URL**. The Management Server will download the file from the
      specified URL, such as ``http://my.web.server/filename.vhd.gz``.

   -  **Zone**. Choose the zone where you want the template to be
      available, or All Zones to make it available throughout
      CloudStack.

   -  **OS Type**: This helps CloudStack and the hypervisor perform
      certain operations and make assumptions that improve the
      performance of the guest. Select one of the following:

      -  If the operating system of the stopped VM is listed, choose it.

      -  If the OS type of the stopped VM is not listed, choose Other.

         .. note:: 
            You should not choose an older version of the OS than the 
            version in the image. For example, choosing CentOS 5.4 to 
            support a CentOS 6.2 image will in general not work. In 
            those cases you should choose Other.

   -  **Hypervisor**: The supported hypervisors are listed. Select the
      desired one.

   -  **Format**. The format of the template upload file, such as VHD or
      OVA.

   -  **Password Enabled**. Choose Yes if your template has the
      CloudStack password change script installed. 
      See :ref:`adding-password-management-to-templates`.

   -  **Extractable**. Choose Yes if the template is available for
      extraction. If this option is selected, end users can download a
      full image of a template.

   -  **Public**. Choose Yes to make this template accessible to all
      users of this CloudStack installation. The template will appear in
      the Community Templates list. See `“Private and
      Public Templates” <#private-and-public-templates>`_.

   -  **Featured**. Choose Yes if you would like this template to be
      more prominent for users to select. The template will appear in
      the Featured Templates list. Only an administrator can make a
      template Featured.


Exporting Templates
-------------------

End users and Administrators may export templates from the CloudStack.
Navigate to the template in the UI and choose the Download function from
the Actions menu.


Creating a Linux Template
-------------------------

Linux templates should be prepared using this documentation in order to
prepare your linux VMs for template deployment. For ease of
documentation, the VM which you are configuring the template on will be
referred to as "Template Master". This guide currently covers legacy
setups which do not take advantage of UserData and cloud-init and
assumes openssh-server is installed during installation.

An overview of the procedure is as follow:

#. Upload your Linux ISO.

   For more information, see `“Adding an
   ISO” <virtual_machines.html#adding-an-iso>`_.

#. Create a VM Instance with this ISO.

   For more information, see `“Creating
   VMs” <virtual_machines.html#creating-vms>`_.

#. Prepare the Linux VM

#. Create a template from the VM.

   For more information, see `“Creating a Template from an Existing 
   Virtual Machine” <#creating-a-template-from-an-existing-virtual-machine>`_.


System preparation for Linux
~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The following steps will prepare a basic Linux installation for
templating.

#. **Installation**

   It is good practice to name your VM something generic during
   installation, this will ensure components such as LVM do not appear
   unique to a machine. It is recommended that the name of "localhost"
   is used for installation.

   .. warning:: 
      For CentOS, it is necessary to take unique identification out of the
      interface configuration file, for this edit
      /etc/sysconfig/network-scripts/ifcfg-eth0 and change the content to
      the following. 

   .. code:: bash

      DEVICE=eth0
      TYPE=Ethernet
      BOOTPROTO=dhcp
      ONBOOT=yes

   The next steps updates the packages on the Template Master.

   -  Ubuntu

      .. code:: bash

         sudo -i
         apt-get update
         apt-get upgrade -y
         apt-get install -y acpid ntp
         reboot

   -  CentOS

      .. code:: bash

         ifup eth0
         yum update -y
         reboot

#. **Password management**

   .. note:: 
      If preferred, custom users (such as ones created during the Ubuntu 
      installation) should be removed. First ensure the root user account 
      is enabled by giving it a password and then login as root to continue.

   .. code:: bash

      sudo passwd root
      logout

   As root, remove any custom user accounts created during the
   installation process.

   .. code:: bash

      deluser myuser --remove-home

   See :ref:`adding-password-management-to-templates` for
   instructions to setup the password management script, this will allow
   CloudStack to change your root password from the web interface.

#. **Hostname Management**

   CentOS configures the hostname by default on boot. Unfortunately
   Ubuntu does not have this functionality, for Ubuntu installations use
   the following steps.

   -  Ubuntu

      The hostname of a Templated VM is set by a custom script in
      `/etc/dhcp/dhclient-exit-hooks.d`, this script first checks if the
      current hostname is localhost, if true, it will get the host-name,
      domain-name and fixed-ip from the DHCP lease file and use those
      values to set the hostname and append the `/etc/hosts` file for
      local hostname resolution. Once this script, or a user has changed
      the hostname from localhost, it will no longer adjust system files
      regardless of it's new hostname. The script also recreates
      openssh-server keys, which should have been deleted before
      templating (shown below). Save the following script to
      `/etc/dhcp/dhclient-exit-hooks.d/sethostname`, and adjust the
      permissions.

      .. code:: bash

         #!/bin/sh
         # dhclient change hostname script for Ubuntu
         oldhostname=$(hostname -s)
         if [ $oldhostname = 'localhost' ]
         then
             sleep 10 # Wait for configuration to be written to disk
             hostname=$(cat /var/lib/dhcp/dhclient.eth0.leases  |  awk ' /host-name/ { host = $3 }  END { printf host } ' | sed     's/[";]//g' )
             fqdn="$hostname.$(cat /var/lib/dhcp/dhclient.eth0.leases  |  awk ' /domain-name/ { domain = $3 }  END { printf     domain } ' | sed 's/[";]//g')"
             ip=$(cat /var/lib/dhcp/dhclient.eth0.leases  |  awk ' /fixed-address/ { lease = $2 }  END { printf lease } ' | sed     's/[";]//g')
             echo "cloudstack-hostname: Hostname _localhost_ detected. Changing hostname and adding hosts."
             echo " Hostname: $hostname \n FQDN: $fqdn \n IP: $ip"
             # Update /etc/hosts
             awk -v i="$ip" -v f="$fqdn" -v h="$hostname" "/^127/{x=1} !/^127/ && x { x=0; print i,f,h; } { print $0; }" /etc/  hosts > /etc/hosts.dhcp.tmp
             mv /etc/hosts /etc/hosts.dhcp.bak
             mv /etc/hosts.dhcp.tmp /etc/hosts
             # Rename Host
             echo $hostname > /etc/hostname
             hostname $hostname
             # Recreate SSH2
             export DEBIAN_FRONTEND=noninteractive
             dpkg-reconfigure openssh-server
         fi
         ### End of Script ###
         
         chmod 774  /etc/dhcp/dhclient-exit-hooks.d/sethostname

   .. warning:: 
      The following steps should be run when you are ready to template 
      your Template Master. If the Template Master is rebooted during 
      these steps you will have to run all the steps again. At the end 
      of this process the Template Master should be shutdown and the 
      template created in order to create and deploy the final template.

#. **Remove the udev persistent device rules**

   This step removes information unique to your Template Master such as
   network MAC addresses, lease files and CD block devices, the files
   are automatically generated on next boot.

   -  Ubuntu

      .. code:: bash

         rm -f /etc/udev/rules.d/70*
         rm -f /var/lib/dhcp/dhclient.*

   -  CentOS

      .. code:: bash

         rm -f /etc/udev/rules.d/70*
         rm -f /var/lib/dhclient/*

#. **Remove SSH Keys**

   This step is to ensure all your Templated VMs do not have the same
   SSH keys, which would decrease the security of the machines
   dramatically.

   .. code:: bash

      rm -f /etc/ssh/*key*

#. **Cleaning log files**

   It is good practice to remove old logs from the Template Master.

   .. code:: bash

      cat /dev/null > /var/log/audit/audit.log 2>/dev/null
      cat /dev/null > /var/log/wtmp 2>/dev/null
      logrotate -f /etc/logrotate.conf 2>/dev/null
      rm -f /var/log/*-* /var/log/*.gz 2>/dev/null

#. **Setting hostname**

   In order for the Ubuntu DHCP script to function and the CentOS
   dhclient to set the VM hostname they both require the Template
   Master's hostname to be "localhost", run the following commands to
   change the hostname.

   .. code:: bash

      hostname localhost
      echo "localhost" > /etc/hostname

#. **Set user password to expire**

   This step forces the user to change the password of the VM after the
   template has been deployed.

   .. code:: bash

      passwd --expire root

#. **Clearing User History**

   The next step clears the bash commands you have just run.

   .. code:: bash

      history -c
      unset HISTFILE

#. **Shutdown the VM**

   Your now ready to shutdown your Template Master and create a
   template!

   .. code:: bash

      halt -p

#. **Create the template!**

   You are now ready to create the template, for more information see
   `“Creating a Template from an Existing Virtual
   Machine” <#creating-a-template-from-an-existing-virtual-machine>`_.

.. note::
   Templated VMs for both Ubuntu and CentOS may require a reboot after 
   provisioning in order to pickup the hostname.


Creating a Windows Template
---------------------------

Windows templates must be prepared with Sysprep before they can be
provisioned on multiple machines. Sysprep allows you to create a generic
Windows template and avoid any possible SID conflicts.

.. note:: 
   (XenServer) Windows VMs running on XenServer require PV drivers, which 
   may be provided in the template or added after the VM is created. The 
   PV drivers are necessary for essential management functions such as 
   mounting additional volumes and ISO images, live migration, and 
   graceful shutdown.

An overview of the procedure is as follows:

#. Upload your Windows ISO.

   For more information, see `“Adding an
   ISO” <virtual_machines.html#adding-an-iso>`_.

#. Create a VM Instance with this ISO.

   For more information, see `“Creating
   VMs” <virtual_machines.html#creating-vms>`_.

#. Follow the steps in Sysprep for Windows Server 2008 R2 (below) or
   Sysprep for Windows Server 2003 R2, depending on your version of
   Windows Server

#. The preparation steps are complete. Now you can actually create the
   template as described in Creating the Windows Template.


System Preparation for Windows Server 2008 R2
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

For Windows 2008 R2, you run Windows System Image Manager to create a
custom sysprep response XML file. Windows System Image Manager is
installed as part of the Windows Automated Installation Kit (AIK).
Windows AIK can be downloaded from `Microsoft Download
Center <http://www.microsoft.com/en-us/download/details.aspx?id=9085>`_.

Use the following steps to run sysprep for Windows 2008 R2:

.. note:: 
   The steps outlined here are derived from the excellent guide by 
   Charity Shelbourne, originally published at `Windows Server 2008 
   Sysprep Mini-Setup. 
   <http://blogs.technet.com/askcore/archive/2008/10/31/automating-the-oobe-process-during-windows-server-2008-sysprep-mini-setup.aspx>`_

#. Download and install the Windows AIK

   .. note:: 
      Windows AIK should not be installed on the Windows 2008 R2 VM you 
      just created. Windows AIK should not be part of the template you 
      create. It is only used to create the sysprep answer file.

#. Copy the install.wim file in the \\sources directory of the Windows
   2008 R2 installation DVD to the hard disk. This is a very large file
   and may take a long time to copy. Windows AIK requires the WIM file
   to be writable.

#. Start the Windows System Image Manager, which is part of the Windows
   AIK.

#. In the Windows Image pane, right click the Select a Windows image or
   catalog file option to load the install.wim file you just copied.

#. Select the Windows 2008 R2 Edition.

   You may be prompted with a warning that the catalog file cannot be
   opened. Click Yes to create a new catalog file.

#. In the Answer File pane, right click to create a new answer file.

#. Generate the answer file from the Windows System Image Manager using
   the following steps:

   #. The first page you need to automate is the Language and Country or
      Region Selection page. To automate this, expand Components in your
      Windows Image pane, right-click and add the
      Microsoft-Windows-International-Core setting to Pass 7 oobeSystem.
      In your Answer File pane, configure the InputLocale, SystemLocale,
      UILanguage, and UserLocale with the appropriate settings for your
      language and country or region. Should you have a question about
      any of these settings, you can right-click on the specific setting
      and select Help. This will open the appropriate CHM help file with
      more information, including examples on the setting you are
      attempting to configure.

      |sysmanager.png|

   #. You need to automate the Software License Terms Selection page,
      otherwise known as the End-User License Agreement (EULA). To do
      this, expand the Microsoft-Windows-Shell-Setup component.
      High-light the OOBE setting, and add the setting to the Pass 7
      oobeSystem. In Settings, set HideEULAPage true.

      |software-license.png|

   #. Make sure the license key is properly set. If you use MAK key, you
      can just enter the MAK key on the Windows 2008 R2 VM. You need not
      input the MAK into the Windows System Image Manager. If you use
      KMS host for activation you need not enter the Product Key.
      Details of Windows Volume Activation can be found at
      `http://technet.microsoft.com/en-us/library/bb892849.aspx 
      <http://technet.microsoft.com/en-us/library/bb892849.aspx>`_

   #. You need to automate is the Change Administrator Password page.
      Expand the Microsoft-Windows-Shell-Setup component (if it is not
      still expanded), expand UserAccounts, right-click on
      AdministratorPassword, and add the setting to the Pass 7
      oobeSystem configuration pass of your answer file. Under Settings,
      specify a password next to Value.

      |change-admin-password.png|

      You may read the AIK documentation and set many more options that
      suit your deployment. The steps above are the minimum needed to
      make Windows unattended setup work.

#. Save the answer file as unattend.xml. You can ignore the warning
   messages that appear in the validation window.

#. Copy the unattend.xml file into the c:\\windows\\system32\\sysprep
   directory of the Windows 2008 R2 Virtual Machine

#. Once you place the unattend.xml file in
   c:\\windows\\system32\\sysprep directory, you run the sysprep tool as
   follows:

   .. code:: bash

      cd c:\Windows\System32\sysprep
      sysprep.exe /oobe /generalize /shutdown

   The Windows 2008 R2 VM will automatically shut down after sysprep is
   complete.


System Preparation for Windows Server 2003 R2
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Earlier versions of Windows have a different sysprep tool. Follow these
steps for Windows Server 2003 R2.

#. Extract the content of \\support\\tools\\deploy.cab on the Windows
   installation CD into a directory called c:\\sysprep on the Windows
   2003 R2 VM.

#. Run c:\\sysprep\\setupmgr.exe to create the sysprep.inf file.

   #. Select Create New to create a new Answer File.

   #. Enter “Sysprep setup” for the Type of Setup.

   #. Select the appropriate OS version and edition.

   #. On the License Agreement screen, select “Yes fully automate the
      installation”.

   #. Provide your name and organization.

   #. Leave display settings at default.

   #. Set the appropriate time zone.

   #. Provide your product key.

   #. Select an appropriate license mode for your deployment

   #. Select “Automatically generate computer name”.

   #. Type a default administrator password. If you enable the password
      reset feature, the users will not actually use this password. This
      password will be reset by the instance manager after the guest
      boots up.

   #. Leave Network Components at “Typical Settings”.

   #. Select the “WORKGROUP” option.

   #. Leave Telephony options at default.

   #. Select appropriate Regional Settings.

   #. Select appropriate language settings.

   #. Do not install printers.

   #. Do not specify “Run Once commands”.

   #. You need not specify an identification string.

   #. Save the Answer File as c:\\sysprep\\sysprep.inf.

#. Run the following command to sysprep the image:

   .. code:: bash

      c:\sysprep\sysprep.exe -reseal -mini -activated

   After this step the machine will automatically shut down


Importing Amazon Machine Images
-------------------------------

The following procedures describe how to import an Amazon Machine Image
(AMI) into CloudStack when using the XenServer hypervisor.

Assume you have an AMI file and this file is called CentOS\_6.2\_x64.
Assume further that you are working on a CentOS host. If the AMI is a
Fedora image, you need to be working on a Fedora host initially.

You need to have a XenServer host with a file-based storage repository
(either a local ext3 SR or an NFS SR) to convert to a VHD once the image
file has been customized on the Centos/Fedora host.

.. note:: 
   When copying and pasting a command, be sure the command has pasted as 
   a single line before executing. Some document viewers may introduce 
   unwanted line breaks in copied text.

To import an AMI:

#. Set up loopback on image file:

   .. code:: bash

      # mkdir -p /mnt/loop/centos62
      # mount -o loop  CentOS_6.2_x64 /mnt/loop/centos54

#. Install the kernel-xen package into the image. This downloads the PV
   kernel and ramdisk to the image.

   .. code:: bash

      # yum -c /mnt/loop/centos54/etc/yum.conf --installroot=/mnt/loop/centos62/ -y install kernel-xen

#. Create a grub entry in /boot/grub/grub.conf.

   .. code:: bash

      # mkdir -p /mnt/loop/centos62/boot/grub
      # touch /mnt/loop/centos62/boot/grub/grub.conf
      # echo "" > /mnt/loop/centos62/boot/grub/grub.conf

#. Determine the name of the PV kernel that has been installed into the
   image.

   .. code:: bash

      # cd /mnt/loop/centos62
      # ls lib/modules/
      2.6.16.33-xenU  2.6.16-xenU  2.6.18-164.15.1.el5xen  2.6.18-164.6.1.el5.centos.plus  2.6.18-xenU-ec2-v1.0  2.6.21.7-2.fc8xen  2.6.31-302-ec2
      # ls boot/initrd*
      boot/initrd-2.6.18-164.6.1.el5.centos.plus.img boot/initrd-2.6.18-164.15.1.el5xen.img
      # ls boot/vmlinuz*
      boot/vmlinuz-2.6.18-164.15.1.el5xen  boot/vmlinuz-2.6.18-164.6.1.el5.centos.plus  boot/vmlinuz-2.6.18-xenU-ec2-v1.0  boot/vmlinuz-2.6.21-2952.fc8xen

   Xen kernels/ramdisk always end with "xen". For the kernel version you
   choose, there has to be an entry for that version under lib/modules,
   there has to be an initrd and vmlinuz corresponding to that. Above,
   the only kernel that satisfies this condition is
   2.6.18-164.15.1.el5xen.

#. Based on your findings, create an entry in the grub.conf file. Below
   is an example entry.

   .. code:: bash

      default=0
      timeout=5
      hiddenmenu
      title CentOS (2.6.18-164.15.1.el5xen)
         root (hd0,0)
         kernel /boot/vmlinuz-2.6.18-164.15.1.el5xen ro root=/dev/xvda 
         initrd /boot/initrd-2.6.18-164.15.1.el5xen.img

#. Edit etc/fstab, changing “sda1” to “xvda” and changing “sdb” to
   “xvdb”.

   .. code:: bash

      # cat etc/fstab
      /dev/xvda  /         ext3    defaults        1 1
      /dev/xvdb  /mnt      ext3    defaults        0 0
      none       /dev/pts  devpts  gid=5,mode=620  0 0
      none       /proc     proc    defaults        0 0
      none       /sys      sysfs   defaults        0 0

#. Enable login via the console. The default console device in a
   XenServer system is xvc0. Ensure that etc/inittab and etc/securetty
   have the following lines respectively:

   .. code:: bash

      # grep xvc0 etc/inittab 
      co:2345:respawn:/sbin/agetty xvc0 9600 vt100-nav
      # grep xvc0 etc/securetty 
      xvc0

#. Ensure the ramdisk supports PV disk and PV network. Customize this
   for the kernel version you have determined above.

   .. code:: bash

      # chroot /mnt/loop/centos54
      # cd /boot/
      # mv initrd-2.6.18-164.15.1.el5xen.img initrd-2.6.18-164.15.1.el5xen.img.bak
      # mkinitrd -f /boot/initrd-2.6.18-164.15.1.el5xen.img --with=xennet --preload=xenblk --omit-scsi-modules 2.6.18-164.15.1.el5xen

#. Change the password.

   .. code:: bash

      # passwd
      Changing password for user root.
      New UNIX password: 
      Retype new UNIX password: 
      passwd: all authentication tokens updated successfully.

#. Exit out of chroot.

   .. code:: bash

      # exit

#. Check `etc/ssh/sshd_config` for lines allowing ssh login using a
   password.

   .. code:: bash

      # egrep "PermitRootLogin|PasswordAuthentication" /mnt/loop/centos54/etc/ssh/sshd_config  
      PermitRootLogin yes
      PasswordAuthentication yes

#. If you need the template to be enabled to reset passwords from the
   CloudStack UI or API, install the password change script into the
   image at this point. See :ref:`adding-password-management-to-templates`.

#. Unmount and delete loopback mount.

   .. code:: bash

      # umount /mnt/loop/centos54
      # losetup -d /dev/loop0

#. Copy the image file to your XenServer host's file-based storage
   repository. In the example below, the Xenserver is "xenhost". This
   XenServer has an NFS repository whose uuid is
   a9c5b8c8-536b-a193-a6dc-51af3e5ff799.

   .. code:: bash

      # scp CentOS_6.2_x64 xenhost:/var/run/sr-mount/a9c5b8c8-536b-a193-a6dc-51af3e5ff799/

#. Log in to the Xenserver and create a VDI the same size as the image.

   .. code:: bash

      [root@xenhost ~]# cd /var/run/sr-mount/a9c5b8c8-536b-a193-a6dc-51af3e5ff799
      [root@xenhost a9c5b8c8-536b-a193-a6dc-51af3e5ff799]#  ls -lh CentOS_6.2_x64
      -rw-r--r-- 1 root root 10G Mar 16 16:49 CentOS_6.2_x64
      [root@xenhost a9c5b8c8-536b-a193-a6dc-51af3e5ff799]# xe vdi-create virtual-size=10GiB sr-uuid=a9c5b8c8-536b-a193-a6dc-51af3e5ff799 type=user name-label="Centos 6.2 x86_64"
      cad7317c-258b-4ef7-b207-cdf0283a7923

#. Import the image file into the VDI. This may take 10–20 minutes.

   .. code:: bash

      [root@xenhost a9c5b8c8-536b-a193-a6dc-51af3e5ff799]# xe vdi-import filename=CentOS_6.2_x64 uuid=cad7317c-258b-4ef7-b207-cdf0283a7923

#. Locate a the VHD file. This is the file with the VDI’s UUID as its
   name. Compress it and upload it to your web server.

   .. code:: bash

      [root@xenhost a9c5b8c8-536b-a193-a6dc-51af3e5ff799]# bzip2 -c cad7317c-258b-4ef7-b207-cdf0283a7923.vhd > CentOS_6.2_x64.vhd.bz2
      [root@xenhost a9c5b8c8-536b-a193-a6dc-51af3e5ff799]# scp CentOS_6.2_x64.vhd.bz2 webserver:/var/www/html/templates/


Converting a Hyper-V VM to a Template
-------------------------------------

To convert a Hyper-V VM to a XenServer-compatible CloudStack template,
you will need a standalone XenServer host with an attached NFS VHD SR.
Use whatever XenServer version you are using with CloudStack, but use
XenCenter 5.6 FP1 or SP2 (it is backwards compatible to 5.6).
Additionally, it may help to have an attached NFS ISO SR.

For Linux VMs, you may need to do some preparation in Hyper-V before
trying to get the VM to work in XenServer. Clone the VM and work on the
clone if you still want to use the VM in Hyper-V. Uninstall Hyper-V
Integration Components and check for any references to device names in
/etc/fstab:

#. From the linux\_ic/drivers/dist directory, run make uninstall (where
   "linux\_ic" is the path to the copied Hyper-V Integration Components
   files).

#. Restore the original initrd from backup in /boot/ (the backup is
   named \*.backup0).

#. Remove the "hdX=noprobe" entries from /boot/grub/menu.lst.

#. Check /etc/fstab for any partitions mounted by device name. Change
   those entries (if any) to mount by LABEL or UUID. You can get that
   information with the blkid command.

The next step is make sure the VM is not running in Hyper-V, then get
the VHD into XenServer. There are two options for doing this.

Option one:

#. Import the VHD using XenCenter. In XenCenter, go to Tools>Virtual
   Appliance Tools>Disk Image Import.

#. Choose the VHD, then click Next.

#. Name the VM, choose the NFS VHD SR under Storage, enable "Run
   Operating System Fixups" and choose the NFS ISO SR.

#. Click Next, then Finish. A VM should be created.

Option two:

#. Run XenConvert, under From choose VHD, under To choose XenServer.
   Click Next.

#. Choose the VHD, then click Next.

#. Input the XenServer host info, then click Next.

#. Name the VM, then click Next, then Convert. A VM should be created.

Once you have a VM created from the Hyper-V VHD, prepare it using the
following steps:

#. Boot the VM, uninstall Hyper-V Integration Services, and reboot.

#. Install XenServer Tools, then reboot.

#. Prepare the VM as desired. For example, run sysprep on Windows VMs.
   See `“Creating a Windows
   Template” <#creating-a-windows-template>`_.

Either option above will create a VM in HVM mode. This is fine for
Windows VMs, but Linux VMs may not perform optimally. Converting a Linux
VM to PV mode will require additional steps and will vary by
distribution.

#. Shut down the VM and copy the VHD from the NFS storage to a web
   server; for example, mount the NFS share on the web server and copy
   it, or from the XenServer host use sftp or scp to upload it to the
   web server.

#. In CloudStack, create a new template using the following values:

   -  URL. Give the URL for the VHD

   -  OS Type. Use the appropriate OS. For PV mode on CentOS, choose
      Other PV (32-bit) or Other PV (64-bit). This choice is available
      only for XenServer.

   -  Hypervisor. XenServer

   -  Format. VHD

The template will be created, and you can create instances from it.


.. _adding-password-management-to-templates:

Adding Password Management to Your Templates
--------------------------------------------

CloudStack provides an optional password reset feature that allows users
to set a temporary admin or root password as well as reset the existing
admin or root password from the CloudStack UI.

To enable the Reset Password feature, you will need to download an
additional script to patch your template. When you later upload the
template into CloudStack, you can specify whether reset admin/root
password feature should be enabled for this template.

The password management feature works always resets the account password
on instance boot. The script does an HTTP call to the virtual router to
retrieve the account password that should be set. As long as the virtual
router is accessible the guest will have access to the account password
that should be used. When the user requests a password reset the
management server generates and sends a new password to the virtual
router for the account. Thus an instance reboot is necessary to effect
any password changes.

If the script is unable to contact the virtual router during instance
boot it will not set the password but boot will continue normally.


Linux OS Installation
~~~~~~~~~~~~~~~~~~~~~

Use the following steps to begin the Linux OS installation:

#. Download the script file cloud-set-guest-password:

   -  `http://download.cloud.com/templates/4.2/bindir/cloud-set-guest-password.in 
      <http://download.cloud.com/templates/4.2/bindir/cloud-set-guest-password.in>`_

#. Copy this file to /etc/init.d.

   On some Linux distributions, copy the file to ``/etc/rc.d/init.d``.

#. Run the following command to make the script executable:

   .. code:: bash

      chmod +x /etc/init.d/cloud-set-guest-password

#. Depending on the Linux distribution, continue with the appropriate
   step.

   On Fedora, CentOS/RHEL, and Debian, run:

   .. code:: bash

      chkconfig --add cloud-set-guest-password


Windows OS Installation
~~~~~~~~~~~~~~~~~~~~~~~

Download the installer, CloudInstanceManager.msi, from the `Download
page <http://sourceforge.net/projects/cloudstack/files/Password%20Management%20Scripts/CloudInstanceManager.msi/download>`_
and run the installer in the newly created Windows VM.


Deleting Templates
------------------

Templates may be deleted. In general, when a template spans multiple
Zones, only the copy that is selected for deletion will be deleted; the
same template in other Zones will not be deleted. The provided CentOS
template is an exception to this. If the provided CentOS template is
deleted, it will be deleted from all Zones.

When templates are deleted, the VMs instantiated from them will continue
to run. However, new VMs cannot be created based on the deleted
template.


.. |sysmanager.png| image:: _static/images/sysmanager.png
   :alt: System Image Manager
.. |software-license.png| image:: _static/images/software-license.png
   :alt: Depicts hiding the EULA page.
.. |change-admin-password.png| image:: _static/images/change-admin-password.png
   :alt: Depicts changing the administrator password