Q. Can I run ESX Server 3.5 in a Hyper-V virtual machine?
A. Currently, the answer seems to be no. Even though ESX doesn’t require hardware virtualization access, it does need to boot from a SCSI disk, which isn’t currently possible with Hyper-V. Hyper-V only allows booting from a virtual IDE device, with SCSI access only for additional disks. You can install ESX server inside VMware Workstation 6.5 and Fusion using a hack in your VMX configuration file.
Q. Does VMware ESX 3.5 require a 64-bit processor with hardware virtualization features?
A. No. VMware ESX server can be installed on a 32-bit x86 processor. During the installation, it will look like Red Hat Linux is being installed. The Red Hat install actually becomes the Service Console, which houses the firewall, apache tomcat, SNMP agent, and other services that are used to manage the virtual machines that run on the VMware Hypervisor.
If you run ESX on an x86 processor, you can still run 64-bit guest OSs thanks to some clever internal mapping in the hypervisor. The ESX 3.5 hypervisor is a 32-bit kernel. In ESX 4.0, the hypervisor is a 64-bit kernel, so it will take better advantage of 64-bit processors. ESX 3.5 doesn’t currently take advantage of the hardware assist technologies (Ring -1) in the Intel and AMD processors. VMware uses binary translation, which they have found gets better performance than the native hardware virtualization in processors. The understanding is that future versions of VMware will utilize some of the hardware virtualization assistance.
Q. What are the types of Virtual Switch available in VMware ESX?
A. Like in Hyper-V, you can create different types of Virtual Switch in ESX. These switches are used for network connectivity, but there are different types of services on ESX which Virtual Switches can be provisioned for.
Upstream, a Virtual Switch can be used by a VMkernel Port, Virtual Machine Port or Service Console Port. A VMkernel port is used for iSCSI and NAS based storage communication in addition to VMotion communications. The Service Console port is used for the service console/management operations and the Virtual Machine port is used as part of a virtual machine configuration to give the virtual machine network access.
Downstream, a Virtual Switch can be connected so there are no physical NICS, which means it creates an internal switch. Only VMs on the ESX host can communicate with each other via the switch, as shown here.
If a Virtual Switch is bound to one physical NIC, you get external connectivity. If you connect multiple physical NICs to a Virtual Switch, ESX automatically creates a NIC teamed Virtual Switch.
It’s possible to have multiple types or ports to the same physical NIC. For example, you could have a Service Console port, VMkernet port and VM port all connected to the same physical NIC. You just need to consider the bottleneck the NIC may become.
Virtual Switches support Virtual LANs (VLANs) which allow connectivity to multiple networks through VLAN tagging. IEEE 802.1Q VLAN tagging is supported. As traffic leaves the Virtual Switch the appropriate VLAN tag is automatically added which is then acted upon by the receiving switch.
Q. What is ESX Server 3i?
A. VMware ESX Server 3i is an embedded hypervisor with a compact 32MB footprint and no reliance on any general purpose OS. 3i is integrated with hardware and typically runs on an internal thumb drive.
3i has a wizard-driven startup that reduces deployment time and can be deploying virtual machines (VMs) in minutes. Additional functionality areas of 3i can be exposed through license activations without any code changes or installations. For example, you can enable VMotion for live VM migrations.
Q. Do VMware vSphere and ESX 4 require a 64-bit processor?
A. Yes. The latest versions of ESX 4 and vSphere require a 64-bit processor. You also need the processor that supports hardware-assisted virtualization (AMD-V or Intel-VT) if you want to run 64-bit virtual machines (VMs). You can run 32-bit VMs without hardware-assisted virtualization, but you still need a 64-bit processor.