• Virtualization with VI3 is the process of installing a hypervisor, a thin layer of software that allows for the separation of the physical hardware from the guest operating system that is typically installed on it.

• Virtualization benefits include fewer physical servers in the data center, which translates into less power consumption, fewer cooling requirements, and in turn less administrative staff to manage all the servers.

• There are four types of virtualization: Bare Metal, Host-based Virtualization, Application Virtualization, and Storage Virtualization.

• A virtual machine creates an x86 or x64 platform that allocates all the needed virtual components to allow for an operating system installation.

• VMware VMs have two main file extensions: .vmx and .vmdk.

• Virtual machine benefits include isolation, encapsulation, hardware independence, and compatibility.

• Virtualization is not an emulation or a simulation; it is a live actual machine running completely in software.

• When you are comparing physical and virtual machines, remember that physical machines have the following limitations:

• When you are comparing physical and virtual machines, virtual machines

• The VMware Infrastructure 3 suite includes the following:

• VMFS is a VMware-developed file system designed solely to run virtual machines and store templates and iso images.

• The VMkernel, also known as the hypervisor, is the software that is installed on the bare metal hardware and thus creates the virtualization layer.

• The Service Console is used to manage ESX Server, but it is also used to help the VMkernel during its boot process.

• The VI client is a Windows-based application that is used to provide a GUI to connect to either an ESX host or to VirtualCenter.

• The VMkernel dictates access to the physical hardware by the Service Console and the virtual machines.

• ESX can be installed on either local storage or SAN-based storage.

• The maximum number of primary disk partitions on an x86 disk is four. You should always partition your disk with three primary partitions and one extended partition, which then allows you to create logical partitions.

• The default size of the /boot partition is 100MB, whereas the / is 5GB.

• The Service Console swap partition should be twice the size of the memory allocated to the Service Console for a maximum of up to 1600MB.

• You can install ESX in either graphical mode or text mode. Text mode should be used over slow WAN links.

• The default size of the vmkcore partition is 100MB.

• You should generally disconnect any SAN LUNs that are attached to ESX prior to installing it to avoid data loss on these LUNs.

• The ESX root password must be at least six characters long.

• ESX 3.5 has three editions (as of this writing): Foundation, Standard, and Enterprise.

• You can license ESX Server in one of the following ways: Evaluation Mode, Serial Number, License Server (Server Based), or Host License File (Host Based).

• VirtualCenter has two editions: VirtualCenter Foundation and VirtualCenter.

• The license key works either per processor or per instance.

• When calculating the per processor licensing, use the number of physical processor sockets available in the server to determine how many licenses you need. So if a processor has dual cores, that does not count toward licenses needed. Calculate only how many processor sockets exist on the server.

• The license server is typically installed on the same server as VirtualCenter but can be installed on a different server. It provides a central repository of licenses and allows for license pooling between ESX hosts that are managed by VirtualCenter.

• If you lose your license server, you have a grace period of 14 days.

• Virtual switches are the inevitable route that all communications inbound or outbound to an ESX host must go through. Virtual switches make up the IP networking backbone of an ESX deployment.

• Virtual switches in ESX 3.5 can have a minimum of 8 ports and a maximum of 1016 ports.

• Virtual switches can be serviced by one or more physical NICs.

• Virtual NICs that connect to virtual switches have their unique MAC address just as every physical NIC connecting to a physical switch has its own unique MAC address.

• Virtual switches support 802.1q or VLAN tagging.

• Virtual switches also support different port groups or connection types.

• Similarities between physical and virtual switches:

• Differences between physical and virtual switches:

• There are three types of virtual switches: internal virtual switch, single adapter virtual switch, and multiadapter virtual switch or NIC teaming.

• You can configure three port group types on a virtual switch: Service Console, VMkernel, and virtual machine.

• ESX has built-in support for 802.1Q or VLAN tagging.

• Three types of Layer 2 security policies can be configured on virtual switches or port groups: promiscuous mode, MAC address changes, and forged transmits.

• You can apply the security policy to either the virtual switch or port group. Policies applied at the port group level take precedence.

• Three configurable settings that help you tweak bandwidth when using traffic shaping are average bandwidth, peak bandwidth, and burst size.

• The four load-balancing policies are Route Based on Originating Port ID, Route Based on Source MAC Hash, Route Based on IP Hash, and Use Explicit Failover.

• You can configure network failover detection based on virtual switch or port groups in one of two ways: link status or beacon probing.

• Notify switches inform physical switches of a change when physical NIC failover occurs or when a new physical NIC is added to a NIC team.

• The failback policy determines what happens when a failed physical NIC is functional again.

• VI3 supports four different types of storage: Local Storage, Fiber Channel, iSCSI, and NAS.

• There are two types of data transfer: Block level, where the LUNs are presented as local storage to the host, or File level, where the server connects to the LUNs similar to a mapped drive.

• Fiber Channel and iSCSI storage allow you to boot ESX from SAN, create VMFS volumes, enable enterprise features, and allow VM access to raw LUNs.

• FC SAN components are an HBA, FC Switch, LUNs, storage systems, and storage processor.

• LUN masking is the process of obscuring or hiding specific LUNs from being visible to hosts.

• Zoning is the compartmentalization of the fabric to break it down into smaller, more secure, and optimally managed subsets with controlled interference.

• Hard zoning and soft zoning are implemented at the Fiber Channel Switch level.

• Fiber Channel addressing is composed of vmhba#:Target#:LUN#:Partition#.

• iSCSI is capable of transmitting SCSI commands over existing Ethernet network infrastructure.

• iSCSI addressing is composed of iqn.date.reversed domain:alias.

• The software initiator driver that is used in ESX is a modified version of the Cisco iSCSI Initiator Command Reference.

• The hardware initiator has all the benefits of the software initiator but also has better performance metrics.

• You can boot ESX to iSCSI only if you are using the hardware initiator.

• Network-attached storage is a self-sufficient storage system, an entity on its own that can be attached via Ethernet to the traditional network.

• ESX 3.5 supports only NFS 3 over TCP.

• NFS datastores support VMotion, DRS, HA, and VCB.

• Virtual Machine File System (VMFS) is a VMware proprietary file system that was designed and optimized to host virtual machines files, templates, and iso images.

• The three types of multipathing are Fixed, MRU, and Round-Robin (experimental as of this writing).

• VirtualCenter to license server communication occurs over ports 27000 and 27010.

• VirtualCenter to ESX Server and ESX Server to ESX Server communication occurs over port 902.

• VirtualCenter architecture is made up of core services, distributed services, additional services, database interface, ESX host management, Active Directory Interface, and VI API.

• The recommended VirtualCenter order is database, license server, VirtualCenter Server, and VI client.

• VirtualCenter adds the following Windows services after installation: VMware Capacity Planner Service, VMware Converter Enterprise Service, VMware Infrastructure Web Access, VMware License Server, VMware Mount Service for VirtualCenter Service, VMware Update Manager Service, and VMware VirtualCenter Server Service.

• The maximum number of VMs per VC server is 2000.

• The maximum number of ESX hosts per VC is 200.

• The maximum number of ESX servers per cluster is 32.

• A virtual machine can have several different virtual hardware components added to it as follows:

• Every VM is made up of a bunch of files as follows:

name_of_VM.vmx,name_of_VM.vmdk, name_of_VM -flat.vmdk, vmware.log, .nvram, vmware-#.log, name_of_VM.vswp, name_of_VM.vmsd.

• Virtual machine snapshots consist of the following files: name_of_VM-00000#-delta.vmdk and name_of_VM-00000#.vmdk.

• The VI security model consists of users, groups, roles, privileges, and permissions.

• The default ESX roles are Read-Only, No Access, and Administrator.

• The default VirtualCenter roles are No Access, Read-Only, Administrator, Virtual Machine Administrator, Datacenter Administrator, Virtual Machine Power User, Virtual Machine User, Resource Pool Administrator, and VCB User.

• VirtualCenter security consists of two types: Local and Active Directory.

• ESX Server security revolves around the Service Console, and because it runs Red Hat Linux, ESX Server security is based on that.

• By default, the following users are assigned the Administrator role in ESX Server: root and vpxuser.

• Three settings control the VM’s CPU and memory resource management: Limit, Reservation, and Shares.

• VMotion requires the following to be successful: access to all datastores, same virtual switch label, access to the same physical networks, compatible CPUs, and gigabit network.

• The three levels of automation for DRS are manual, partially automated, and fully automated.

• DRS allows you to set rules that govern whether VM can exist on the same ESX host at the same time or if they should always be separated. These are the Affinity and Anti-Affinity rules.

• A virtual machine can be configured with one, two, or four vCPUs.

• The number of Hardware Execution Contexts equals the number of physical processors available in your system. A dual single-socket quad-core system is equal to 4 H.E.C.

• Hyperthreading is an Intel Corporation technology that allows you to schedule multiple threads on the same processor at the same time.

• The VMkernel has at its disposal several different techniques and concepts by which it can control and leverage virtual memory as follows: transparent memory page sharing, balloon-driver or vmmemctl, and VMkernel swap.

• You can back up a VM by installing an agent inside the guest operating system or installing an agent inside the SC or using VCB.

• You can back up the ESX host either by installing an agent inside the Service Console or using third-party imaging tools.

• By using VCB, you have the following advantages: no backup window needed, backup load is moved away from the ESX host, and backup agent is optional.

• VMware HA maintains a communication channel with all the other ESX hosts that are members of the same cluster; it does that using a heartbeat that it sends out every 15 seconds or 15000 milliseconds.

• Virtual Machine Failure Monitoring is a technology that is disabled by default. Its function is to monitor virtual machines, which it queries every 20 seconds via a heartbeat.

• HA requires some configuration prerequisites before it will function properly. The following must be met: VirtualCenter, DNS Resolution, access to shared storage, and access to the same network.

• You can configure SC redundancy in one of two ways: create two Service Console port groups or assign two physical NICs in the form of a NIC team to the Service Console vSwitch.

• ESX supports three types of clustering scenarios for VMs: cluster-in-a-box, cluster-across-boxes, and physical-to-virtual-cluster.