Generating VM templates

Using Abiquo you are able to manage several hypervisors from the same management interface. And you can also deploy the same virtual appliance in different hypervisors. This section provides a list of best practices to achieve maximum compatibility of virtual machine templates.

Best practices for hypervisor compatibility

You can use any virtual disk as a template to deploy machines in Abiquo, if it is one of the supported formats. You can install an operating system on a virtual machine deployed directly on a hypervisor, and then distribute the virtual disk file. This virtual disk file is called a virtual machine template. To ensure that your virtual machine template works perfectly, before you distribute it, you should follow these steps on the virtual machine you are generating the template from.

Disks

Use IDE system disks

Abiquo attaches virtual machine system disks to IDE controllers on all hypervisors, so Abiquo recommends that you create IDE system disks.

VMware hypervisors can deploy virtual machines with SCSI system disks if this functionality is configured using Abiquo configuration properties. See the VMware configuration page in the Admin Guide.

Use the LSILogic SCSI virtual controller

When Abiquo deploys virtual machines, it adds the LSILogic SCSI controller for the iSCSI volumes used for virtual storage and persistent virtual machines.
LSILogic is the most common virtual SCSI controller used by hypervisors and Abiquo recommends this controller for your virtual machines.

Networks

Choose E1000 network cards as your virtual network adapters

Intel E1000 compatible network cards can be found in the list of available hardware of all the hypervisors Abiquo supports. If you want to run your virtual appliances in different hypervisors, use E1000.

Two new types of network card were introduced in Abiquo v2.0.

Configure networking to use DHCP

Abiquo works with an embedded DHCP server that controls the IP leases according to the specifications of the virtual machine in the interface. For the machines to receive their IP addresses correctly, the Machine Templates you deploy should have dynamically-assigned IP addresses in their default configuration. Otherwise they will be receiving the same static IP the machine had while the template was being generated, leading to possible conflicts or, most likely, out of range addresses.

Erase MAC addresses from network scripts

Some operating systems store the MAC addresses in their network initialization scripts. This happens, for example, in Red-Hat-based Linux systems such as Fedora and CentOS. This is not correct: when a template is deployed to create a virtual machine, a new MAC address is assigned but the content of the network scripts is always the same, and if both the current MAC and the one specified in the script do not match, the network script will fail, leaving the network interface down. To ensure this does not happen, we need to erase all trace of physical addresses in the network scripts.

Virtual disk file formats

Use VMDK monolithic flat to build your template

VMDK monolithic flat format can be used in several hypervisors without any conversion. If access to the template file is local, this is the best format to use.

Distribute templates in a compressed format

Virtual Machine Templates can be very large and flat formats can have a size equal to the total virtual disk capacity. To minimize download overhead when distributing a virtual machine template from a remote template repository, convert it to a compressed format like VMDK-streamOptimized or QCOW2-compressedSparse.

Other compatible hardware devices

For information about hardware devices that are compatible with Abiquo, please see OVF reference.