Install Hypervisors

Eucalyptus deploys VM instances on a hypervisor. A hypervisor is a software abstraction of a physical hardware platform that enables multiple guest operating systems to run concurrently on a single physical machine. Eucalyptus is directly compatible with both Xen and KVM hypervisors. To interact with these hypervisors, Eucalyptus uses the libvirt virtualization API. Alternatively, you can configure Eucalyptus to use VMware virtualization technologies with which it communicates using web services.

While it is usually possible to use Xen and KVM with any of the supported distributions, the level of effort necessary, and the quality of the resulting platform for different distribution-hypervisor combinations varies. Before choosing an open source hypervisor and a Linux distribution, we recommend that you consider the level of support that the community reports for a specific combination.

Eucalyptus supports the Xen hypervisor for CentOS 5 and RHEL 5, and KVM for CentOS 6, RHEL 6 and Ubuntu.

Important

Be sure to set the ulimit parameter to an appropriately large value if you expect to launch a large number of instances on the Node Controller. For example: ulimit -u 63652

CentOS 5

Tip

Skip this section if you selected Virtualization as an option when you installed the kernel.

Before installing Eucalyptus, make sure that each NC server has a kernel with Xen support, and that this is the default kernel loaded at boot time.

To determine the current kernel, enter the following command on an NC server:

uname -r | grep xen | wc -l

If the command returns a zero, the Xen kernel is either not installed or not setup correctly. You must install a Xen kernel.

To install a Xen kernel:

Log in to a host you plan to use as an NC.
Confirm that YUM is working.
Install the Xen kernel package.
```
yum install kernel-xen 
```
Ensure that grub is set up to boot the Xen kernel by default. For example, edit /boot/grub/menu.lst and change:
```
default 1
```
to:
```
default 0
```
Repeat on each planned NC in your system.

CentOS 6

When you install Eucalyptus from packages, KVM will be installed on all NCs. For more information about using KVM on CentOS 6, go to the Virtualization page.

RHEL 5

Tip

Skip this section if you selected Virtualization as an option when you installed the kernel.

Before installing Eucalyptus, make sure that each NC server has a kernel with Xen support, and that this is the default kernel loaded at boot time.

To determine the current kernel, enter the following command on an NC server:

uname -r | grep xen | wc -l

If the command returns a zero, the Xen kernel is either not installed or not setup correctly. You must install a Xen kernel.

To install a Xen kernel:

Log in to a host you plan to use as an NC.
Confirm that YUM is working.
Make sure that you have set up the required entitlements for RHN access.
Install the Xen kernel package.
```
yum install kernel-xen 
```
Repeat on each planned NC in your system.

RHEL 6

When you install Eucalyptus from packages, KVM will be installed on all NCs. For more information about using KVM on RHEL 6, go to the Virtualization page in the Red Hat documentation.

Ubuntu 10.04 LTS

When you install Eucalyptus from packages, KVM will be installed on all NCs. For more information about installing and using KVM on Ubuntu, go to the KVM page in the Ubuntu documentation.

Ubuntu 12.04 LTS

When you install Eucalyptus from packages, KVM will be installed on all NCs. For more information about installing and using KVM on Ubuntu, go to the KVM page in the Ubuntu documentation.