Before you can run OpenStack with XCP or XenServer, you must install the software on an appropriate server. Xen is a type 1 hypervisor: When your server starts, Xen is the first software that runs. Consequently, you must install XenServer or XCP before you install the operating system on which you want to run OpenStack code. The OpenStack services then run in a virtual machine that you install on top of XenServer. Before you can install your system you must decide if you want to install Citrix XenServer (either the free edition, or one of the paid editions) or Xen Cloud Platform from Xen.org. You can download the software from the following locations: http://www.citrix.com/XenServer/download http://www.xen.org/download/xcp/index.html When installing many servers, you may find it easier to perform PXE boot installations of XenServer or XCP. You can also package up any post install changes you wish to make to your XenServer by creating your own XenServer supplemental pack. It is also possible to get XCP by installing the xcp-xenapi package on Debian based distributions. However, this is not as mature or feature complete as above distributions. This will modify your boot loader to first boot Xen, then boot your existing OS on top of Xen as Dom0. It is in Dom0 that the xapi daemon will run. You can find more details on the Xen.org wiki: http://wiki.xen.org/wiki/Project_Kronos Ensure you are using the EXT type of storage repository (SR). Features that require access to VHD files (such as copy on write, snapshot and migration) do not work when using the LVM SR. Storage repository (SR) is a XenAPI specific term relating to the physical storage on which virtual disks are stored. On the XenServer/XCP installation screen, this is selected by choosing "XenDesktop Optimized" option. In case you are using an answer file, make sure you use srtype="ext" within the installation tag of the answer file.

You are now ready to install OpenStack onto your XenServer system. This process involves the following steps: For resize and migrate functionality, please perform the changes described in the Configuring Resize section of the OpenStack Configuration Reference. Install the VIF isolation rules to help prevent mac and ip address spoofing. Install the XenAPI plugins - see the next section. To support AMI type images, you must set up /boot/guest symlink/directory in Dom0. For detailed instructions, see next section. To support resize/migration, set up an ssh trust relation between your XenServer hosts, and ensure /images is properly set up. See next section for more details. Create a Paravirtualized virtual machine that can run the OpenStack compute code. Install and configure the nova-compute in the above virtual machine. For further information on these steps look at how DevStack performs the last three steps when doing developer deployments. For more information on DevStack, take a look at the DevStack and XenServer Readme. More information on the first step can be found in the XenServer mutli-tenancy protection doc. More information on how to install the XenAPI plugins can be found in the XenAPI plugins Readme.

XenServer, through the XenAPI integration with OpenStack provides a feature to boot instances from an ISO file. To activate the "Boot From ISO" feature, you must configure the SR elements on XenServer host that way. Create an ISO-typed SR, such as an NFS ISO library, for instance. For this, using XenCenter is a simple method. You must export an NFS volume from a remote NFS server. Make sure it is exported in read-write mode. On the compute host, find the uuid of this ISO SR and write it down. # xe host-list Locate the uuid of the NFS ISO library: # xe sr-list content-type=iso Set the uuid and configuration. Even if an NFS mount point isn't local storage, you must specify "local-storage-iso." # xe sr-param-set uuid=[iso sr uuid] other-config:i18n-key=local-storage-iso Make sure the host-uuid from "xe pbd-list" equals the uuid of the host you found earlier: # xe sr-uuid=[iso sr uuid] You can now add images via the OpenStack Image Registry, with disk-format=iso, and boot them in OpenStack Compute. # glance image-create --name=fedora_iso --disk-format=iso --container-format=bare < Fedora-16-x86_64-netinst.iso