o When you remediate hosts against baseline groups containing upgrade & patch baselines, the upgrade is performed first. Host upgrade in a
high-latency network in which Update Manager & the hosts are at different locations might take a few hours because the upgrade file is
copied from the Update Manager server repository to the host before the upgrade.
o When you upgrade a host, no third-party management agents or software applications are migrated to the ESX 4.0/ESXi 4.0 host. 220 702
o In the ESX 3.5 patch remediation process, cumulative rollups & updates are considered patches. If a rollup contains two patches installed on
the host, the state of the host is noncompliant against the rollup until the rollup itself is installed on the host.
o In the ESX 4.0 patch remediation process, Update Manager operates with vSphere Installation Bundles (*.vib files). A bundle is the smallest
installable unit on an ESX 4.x host. A bulletin defines a specific fix for a host, a rollup that aggregates previous fixes, or an update release.
When a host is compliant with all bundles in a bulletin, it is compliant with the vSphere bulletin that contains the bundles.
o Before the ESX host upgrade remediation, Update Manager runs a script on the host to check whether the host can be upgraded. If the host
can be upgraded, Update Manager copies the ISO file to the host. The ISO file contains the bits that are to be installed as well as a Linux kernel
& ramdisk, which serve as the installer environment. The host reboots into the installer, & the installer creates a service console virtual disk
(VMDK) to install the packages into the console VMDK. The host is rebooted, upgraded to ESX 4.0, & reconnected to the vCenter system. If the
upgrade fails, you can roll back to the previous version.
o For ESXi hosts, updates are all-inclusive.
o The ESXi image on the host maintains two copies. The first copy is in the active boot & the second one is the standby boot.
o The active boot contains the patched image & the standby boot contains the previous version of the ESXi host image.
o Take snapshots of templates before remediation, especially if the templates are sealed.
o After a template is started & remediated, the registry keys are restored, & the machine is shut down, returning the template to its sealed
state.
o Staging patches for ESX/ESXi hosts allows you to download the patches from the Update Manager server to the ESX/ESXi hosts, without
applying the patches immediately.
o Staging patches does not require that the hosts enter maintenance mode.
o Update Manager stores data about events. You can review this event data to gather information about operations that are in progress or that
have finished.
o Because of limitations in the ZIP utility used by the Update Manager, the cumulative log file size cannot exceed 2GB, although the script seems
to complete successfully. 9L0-403
o To generate Update Manager log files, exclude the generation of the vCenter logs using the vumsupport. wsf script file:
o C:\Program Files\VMware\Infrastructure\Update Manager\cscript vum-support.wsf /n
o When you upgrade an ESXi host with less than 10MB of free space in its /tmp directory, although Update Manager indicates that the
remediation process completes successfully, the ESXi host is not upgraded.
vCenter Converter Administration Guide
o vCenter Converter does not support creating thin-provisioned target disks on ESX/ESXi 4.0.
o vCenter Converter Components:
o vCenter Converter server
o vCenter Converter CLI
o vCenter Converter agent
o vCenter Converter client
o vCenter Converter Boot CD
o When you import a physical system, vCenter Converter uses cloning & system reconfiguration steps.
o When you hot clone dual-boot systems, you can clone only the default operating system to which the boot.ini file points.
o You can clone remotely, as long as it is running & accessible to the network. With local cloning, vCenter Converter runs on the source machine
to perform the migration.
o During hot cloning, the machine you are cloning experiences no downtime.
o Disk-based cloning for cold cloning & importing existing VMs. Supports all basic & dynamic disks.
o Volume-based cloning for hot & cold cloning & for importing existing VMs. All volumes in the destination VM are basic volumes, performed at
the file level or block level, depending on your size selections.
o Only master boot record (MBR) disks are supported. GUID partition table (GPT) disks are not supported.
o Hot cloning supports all types of source volumes that Windows recognizes.
o You cannot schedule reconfiguration tasks.
o Converter can restore VCB images of any guest operating system type on an ESX/ESXi host that vCenter Server manages. However, only disks
9L0-510

are preserved. It does not preserve certain hardware backup information from the original image, but rather substitutes default settings.
o You can schedule an unlimited number of physical-to-virtual recurring tasks & specify how the existing VMs are to be retained.For recurring
tasks, the vCenter Converter agent must be installed permanently on the source machine.
o You can keep multiple VMs as backups to an existing machine
o VM names have an 80-character limit. VMware recommends a maximum of 60 characters because the time stamp might make the name
exceed the limit.
o Applications might not work if they depend on specific characteristics of the underlying hardware.

ESX4 Patch Management Guide
o Bulletin - grouping of one or more VIBs (vSphere Installation Bundle).
o Depot - logical grouping of VIBs – online.
o Offline Bundle zip - archive that encapsulates VIBs.
o Patch - bulletin that groups one or more VIBs together to address a particular issue or enhancement.
o Roll-up - collection of patches that is grouped for ease of download and deployment.
o Update - periodic release of an ESX image.
o VIB - single software package.
o A record of each installed bulletin is written to the /etc/vmware/esxupdate
o Four basic modes of esxupdate:
o Inspection mode 220 701
o esxupdate query - display a list of bulletins installed.
o esxupdate info - display information on the contents of one or more bulletins.
o Scan mode - determines which bulletins are applicable.
o Test mode - go through all installation operations without installing.
o Update mode - installs bulletins.
o The installation process is recorded in the esxupdate.log file. By default, this file is located in the /var/log/vmware directory.
o esxupdate never reboots your host.
Optional vSphere Products and Modules
vCenter Update Manager Administration Guide
o Update Manager can:
o Scan for compliance & apply updates for guests, appliances, & hosts.
o Directly upgrade hosts, VM hardware, VMware Tools, & virtual appliances.
o Update third-party software on hosts.
o Update Manager requires network connectivity with vCenter. Each installation of the Update Manager must be associated (registered) with a
single vCenter instance
o The Update Manager Client has two main views, Administrator’s view & Compliance view.
o Administrator’s view you can:
o Configure the Update Manager settings
o Create & manage baselines & baseline groups
o View Update Manager events
o Review the patch repository & add or remove patches from a baseline
o Compliance view you can: 220 702
o View compliance & scan results for each selected inventory object
o Attach & detach baselines & baseline groups from a selected inventory object
o Scan a selected inventory object
o Stage patches for hosts
o Remediate a selected inventory object
o The Update Manager process begins by downloading information about a set of security patches. One or more of these patches are
aggregated to form a baseline. Multiple baselines can be added to a baseline group. A baseline group is a composite object that consists of a
set of non-conflicting baselines. You can use baseline groups to combine different types of baselines & then scan & remediate an inventory
object against all of them as a whole. If a baseline group contains both upgrade & patch baselines, the upgrade executes first.
o A collection of VMs, virtual appliances, & ESX/ESXi hosts or individual inventory objects can be scanned for compliance with a baseline or a
baseline group & later remediated (updated). You can initiate these processes manually or through scheduled tasks.
o You can configure the Update Manager server to download patches either from the Internet or from a shared repository.
o Types of scan:
o Patch scan – ESX 3.0.3 & later, ESX 3i version 3.5 & later, VMs running Windows or Linux.
o Host upgrade scan – ESX 3.0.0 & later & ESX 3i version 3.5 & later.
o VMware Tools scan –Windows or Linux.
o VM hardware upgrade scan.
220 701

o Virtual appliance upgrade scan –VMware Studio registered Red Hat, Ubuntu, SUSE, & CentOS Linux virtual appliances.
o Staging patches for ESX/ESXi 4.0 hosts allows you to download the patches from the Update Manager server to the ESX/ESXi hosts without
applying the patches immediately.
o Remediation applies patches & upgrades after a scan is complete.
o Baselines can be:
o Upgrade

o vSphere CLI commands:
Command ESXi 4 ESX 4 VC 4 CLI “esxcfg”
prefix available
Description
esxcli yes yes no Manage pluggable storage architecture (PSA) & native multipathing (NMP).
resxtop yes yes yes Monitors in real time how ESX hosts use resources. Runs in interactive or
batch mode. This command is supported only on Linux.
svmotion no no yes Moves a VM’s configuration file & optionally its disks while the VM is
running. Must run against a vCenter Server system. 640 802 Dumps
vicfg-advcfg yes yes yes esxcfg-advcfg Performs advanced configuration including enabling & disabling CIM
providers. Use this command as instructed by VMware.
vicfg-cfgbackup yes no no esxcfg-cfgbackup Backs up the configuration data of an ESXi system & restores previously
saved configuration data.
vicfg-dns yes yes yes esxcfg-dns Specifies an ESX/ESXi host’s DNS (Domain Name Server) configuration.
vicfg-dumppart yes yes yes esxcfg-dumppart Manages diagnostic partitions.
vicfg-iscsi yes yes yes Manages iSCSI storage.
vicfg-module yes yes yes esxcfg-module Enables VMkernel options. Use this command with the options listed in this
document, or as instructed by VMware.
vicfg-mpath yes yes yes esxcfg-mpath Configures storage arrays.
vicfg-mpath35 no no no Configures storage arrays for ESX/ESXi 3.5 hosts.
vicfg-nas yes yes yes esxcfg-nas Manages NAS file systems
vicfg-nics yes yes yes esxcfg-nics Manages the ESX/ESXi host’s physical NICs.
vicfg-ntp yes yes yes esxcfg-ntp Specifies the NTP (Network Time Protocol) server.
vicfg-rescan yes yes yes esxcfg-rescan Rescans the storage configuration.
vicfg-route yes yes yes esxcfg-route Manipulates the ESX/ESXi host’s route entry
vicfg-scsidevs yes yes yes esxcfg-scsidevs Finds available LUNs.
vicfg-snmp yes yes no esxcfg-snmp Manages the Simple Network Management Protocol (SNMP) agent.
vicfg-syslog yes no yes esxcfg-syslog Specifies the syslog server & the port to connect to that server for ESXi
hosts. 640-802640 802 braindumps
License Server Configuration for vCenter Server 4.0 – ESX 3.x licensing
o Using vCenter Server 4.0 to manage ESX 3.x/ESXi 3.5 hosts, you have several options:
o A single license server for vCenter Server 4.0 and the ESX 3.x/ESXi 3.5 hosts.
o One license server for vCenter Server 4.0, and use another license server for the ESX 3.x/ESXi 3.5 hosts.
o A license server for vCenter Server 4.0, and use host-based licensing for the ESX 3.x/ESXi 3.5 hosts.
o Do not use a license server. Upgrade all of your hosts to ESX 4.0/ESXi 4.0.

o Optimize for performance – Acknowledges changes to the virtual disk immediately, but saves them at a later time.
o VMI currently supports only 32-bit guests.
Additional Resources
Setup for Failover Clustering and Microsoft Cluster Service
o Support for Windows Server 2003 SP2, 2000 SP4, or 2008.
o Only two-node clustering.
Storage Type Cluster in a Box Cluster Across Boxes Standby Host
(n+1) vcp 4
Virtual disks Yes (recommended) No No
Non-pass-through RDM (virtual compatibility mode) Yes Yes No
Pass-through RDM (physical compatibility mode) No Yes (recommended) Yes
o Clusters across physical machines with non-pass-through RDM is supported only for clustering with Windows 2000 Server or Windows Server
2003. It is not supported for clustering with Windows Server 2008.
o Not supported:
o Clustering on iSCSI or NFS disks.
o Clustered virtual machines as part of VMware clusters (DRS or HA).
o MSCS in conjunction with VMware Fault Tolerance.
o Migration with VMotion.
o N-Port ID Virtualization (NPIV)
o With native multipathing (NMP), clustering is not supported when the path policy is set to round robin.
o You must use hardware version 7 with ESX4.
o You can put the boot disk of a virtual machine on a SAN-based VMFS volume.
o Clustered continuous replication (CCR) environment for Microsoft Exchange - Use physical compatibility mode RDMs.
o For boot disks - Select “Support clustering features such as Fault Tolerance” to create a disk in eagerzeroedthick format.
o SCSI Controller Type:
o Windows 2000 and 2003 - Server LSI Logic Parallel (download from the LSI web site).
o Windows 2008 - LSI Logic SAS
o Cluster across boxes:
o Shared storage must be on an FC SAN.
o RDM in physical compatibility (pass-through) or virtual compatibility (non-pass-through) mode. VMware recommends physical vmware vcp 4
compatibility mode. The cluster cannot use virtual disks for shared storage.
o Failover clustering with Windows Server 2008 is not supported with virtual compatibility mode
o Standby Host (n+1): Use only a single physical path from the host to the storage arrays.
vSphere Command-Line Interface Installation and Reference Guide
o vSphere CLI commands run on top of the vSphere SDK for Perl.
o You can install a vSphere CLI package on either Linux or Microsoft Windows, or deploy the vSphere Management Assistant (vMA).
o If you establish a vCenter Server system as a target server, you can execute most vSphere CLI commands against all ESX/ESXi systems it
manages without additional authentication.
o You can use vSphere CLI commands interactively or in scripts.
o The installation script for the vSphere CLI is supported on:
o Red Hat Enterprise Linux (RHEL) 5.2 (64 bit)
o Red Hat Enterprise Linux (RHEL) 5.2 (32 bit)
o SUSE Enterprise Server 10 SP1 32 bit
o Ubuntu 8.04 32 bit
o vSphere CLI is supported on:
o Windows XP SP2 32 bit
o Windows XP SP2 64 bit
o Windows Vista Enterprise SP1 32 bit
o Windows Vista Enterprise SP1 64 bit 640 802
o If you set up a vCenter Server system as a target server, you can specify any of the ESX/ESXi hosts that vCenter Server system manages using
the –vihost option.
o VMware recommends that you use the vSphere CLI commands with the vicfg prefix. Commands with the esxcfg prefix are available mainly for
compatibility reasons & might become obsolete.

o VMware HA Attributes:
Attribute Description
das.isolationaddress[…} Address to ping to determine if a host is isolated from the network. If not specified, the default
gateway of the console network is used. Can specify multiple isolation addresses (up to 10).
das.usedefaultisolationaddress Specifies whether or not this default is used (true|false).
das.failuredetectiontime Failure detection time for host monitoring. The default is 15000 milliseconds
das.failuredetectioninterval Heartbeat interval among VMware HA hosts. Default is 1000 milliseconds.
das.defaultfailoverhost The host that VMware HA tries to fail virtual machines over to.
das.isolationShutdownTimeout Time the system waits for a VM to shut down before powering it off. Default is 300 seconds. vcp-410
das.slotMemInMB The maximum bound on the memory slot size.
das.slotCpuInMHz The maximum bound on the CPU slot size.
das.vmMemoryMinMB Memory resource value assigned to a VM if it’s not specified or zero. Default is 0 MB.
das.vmCpuMinMHz Default CPU resource value assigned to a VM if it’s not specified or zero. Default is 256MHz.
das.iostatsInterval I/O stats interval for VM monitoring sensitivity. Default is 120 (seconds).
o If you change the value of any of the following advanced attributes, you must disable and then re-enable VMware HA before your changes
take effect.
o das.isolationaddress[…]
o das.usedefaultisolationaddress
o das.failuredetectiontime
o das.failuredetectioninterval
o das.isolationShutdownTimeout
o On ESX hosts, HA communications travel over service console networks.
o On ESXi hosts, HA communications travel over VMkernel networks.
o HA needs and automatically opens the following firewall ports:
o Incoming port: TCP/UDP 8042-8045
o Outgoing port: TCP/UDP 2050-2250
o VMware Fault Tolerance provides continuous availability for virtual machines by creating and maintaining a Secondary VM that is identical to,
and continuously available to replace, the Primary VM in the event of a failover situation.
o A fault tolerant VM and its secondary copy are not allowed to run on the same host. Fault Tolerance uses anti-affinity rules.
o Fault Tolerance prerequisites:
o VMware HA must be enabled on the cluster. Host Monitoring should also be enabled.
o Host certificate checking must be enabled for all hosts.
o Each host must have a VMotion and a Fault Tolerance Logging NIC configured.
o Hosts must have the same version and patch level.
o Hosts must have processors from the FT-compatible processor group.
o Hosts must have Hardware Virtualization (HV) enabled in the BIOS.
o Virtual machines must be stored in vmware vcp 410 virtual RDM or VM disk (VMDK) files that are thick provisioned with the Cluster Features option.
o Virtual machines must be running on one of the supported guest operating systems.
o Not supported for fault tolerant virtual machines.
o Snapshots.
o Storage VMotion
o DRS features
o SMP virtual machines
o Physical RDMs
o Paravirtualized guests
o NPIV
o NIC passthrough
o EPT/RVI
o You should have no more than four fault tolerant virtual machines (primaries or secondaries) on any single host.
o The recommendation is that you use a maximum of 16 virtual disks per fault tolerant virtual machine.
Appendix – Fault Tolerance Error Messages
vSphere Web Access Administrator’s Guide
o Supported Operating Systems:
o Windows 2003 SP1, XP Pro SP3, XP Home SP2, 2000 SP4
o Linux with standard libraries, but requiring GTK+ 2.
o Supported browsers:
o IE 6, 7 or later
o Firefox 2, 3.0 or later vmware vcp 410
o The console webAccess service is now vmware-webAccess
o The Alarms tab is available only when you use vSphere Web Access to connect to vCenter Server.
o You can view the assigned tasks for a virtual machine, but you cannot assign tasks using Web Access.
o New disk policy (not available option from vSphere Client)
o Optimize for safety – Saves all changes to the virtual disk before notifying the system.

o Periodically (every two seconds by default), the system examines the loads of the various nodes and determines if it should rebalance the load
by moving a virtual machine from one node to another.
o Transparent page sharing has also been optimized for use on NUMA systems.
o The VMkernel.Boot.sharePerNode option controls whether memory pages can be shared (de-duplicated) only within a single NUMA node or Passed VCP410
across multiple NUMA nodes. It is turned on by default.
o If you turn off the option, identical pages can be shared across different NUMA nodes. In memory-constrained environments, such as VMware
View this could be very beneficial.
o The systems that offer a NUMA platform include AMD CPUs or the IBM Enterprise X-Architecture.
o You must manually select the boxes for all processors in the NUMA node. CPU affinity is specified on a per-processor, not on a per-node, basis.
o Specify nodes to be used for future memory allocations only if you have also specified CPU affinity.
Appendix A - Performance Monitoring Utilities: resxtop and esxtop
o The esxtop utility reads its default configuration from .esxtop4rc.
o Do not edit the .esxtop4rc file. Instead, select the fields and the order in a running esxtop process, make changes, and save this file using
the W interactive command.
Appendix B – Advanced attributes
vSphere Availability Guide
o The first five hosts added to the cluster are designated as primary hosts, and all subsequent hosts are designated as secondary hosts. The
primary hosts maintain and replicate all cluster state and are used to initiate failover actions. If a primary host is removed from the cluster,
VMware HA promotes another host to primary status.
o One of the primary hosts is also designated as the active primary host and its responsibilities include:
o Deciding where to restart virtual machines.
o Keeping track of failed restart attempts.
o Determining when it is appropriate to keep trying to restart a virtual machine.
o If the active primary host fails, another primary host replaces it.
o If a host stops receiving heartbeats from all other hosts in the cluster for more than 12 seconds, it attempts to ping its isolation addresses. If
this also fails, the host declares itself as isolated from the network.
o Three types of admission control:
o Host
o Resource pool
o HA Passed VCP 4
o Only VMware HA admission control can be disabled.
o Slot size is a logical representation of the memory and CPU resources that satisfy the requirements for any powered-on virtual machine in the
cluster.
o The maximum Configured Failover Capacity that you can set is four.
o If your cluster contains any virtual machines that have much larger reservations than the others, they will distort slot size calculation. To avoid
this, you can specify an upper bound for the CPU or memory component of the slot size by using the das.slotCpuInMHz or das.slotMemInMB
advanced attributes, respectively.
o You can configure VMware HA to perform admission control by reserving a specific percentage of cluster resources for recovery from host
failures.
o You can configure VMware HA to designate a specific host as the failover host.
o To ensure that spare capacity is available on the failover host, you are prevented from powering on virtual machines or using VMotion to
migrate virtual machines to the failover host.
o When choosing an admission control policy, you should consider a number of factors:
o Avoiding Resource Fragmentation - The Host Failures Cluster Tolerates policy avoids resource fragmentation by defining a slot as the
maximum virtual machine reservation. The Percentage of Cluster Resources policy does not address the problem of resource
fragmentation. With the Specify a Failover Host policy, resources are not fragmented because a single host is reserved for failover.
o Flexibility of Failover Resource Reservation - The Host Failures Cluster Tolerates policy allows you to set the failover level from one to four
hosts. The Percentage of Cluster Resources policy allows you to designate up to 50% of cluster resources for failover. The Specify a
Failover Host policy only allows you to specify a single failover host.
o Heterogeneity of Cluster - In a heterogeneous cluster, the Host Failures Cluster Tolerates policy can be too conservative because it only vcp 410
considers the largest virtual machine reservations when defining slot size and assumes the largest hosts fail when computing the Current
Failover Capacity. The other two admission control policies are not affected by cluster heterogeneity.

o ESX/ESXi uses at least 50MB of system memory for the VMkernel. This is not configurable. It depends on the number and type of PCI devices.
An ESXi host uses additional system memory for management agents.
o The service console typically uses 272MB.
o Memory activity is monitored to estimate the working set sizes for a default period of 60 seconds.
o ESX/ESXi charges more for idle memory than for memory that is in use. This is done to help prevent virtual machines from hoarding idle
memory. VCP-410 questions
o Hosts can reclaim memory from virtual machines using:
o Memory balloon driver (vmmemctl) - collaborates with the server to reclaim pages that are considered least valuable by the guest
operating system. Closely matches the behavior of a native system under similar memory constraints. Causes the guest to use its own
native memory management algorithms. You must configure the guest operating system with sufficient swap space.
o Swap Files - hosts use swapping to forcibly reclaim memory from a virtual machine when the vmmemctl driver is not available or is not
responsive. You must reserve swap space for any unreserved virtual machine memory (the difference between the reservation and the
configured memory size) on per-virtual machine swap files.
o If you are overcommitting memory, to support the intra-guest swapping induced by ballooning, ensure that your guest operating systems also
have sufficient swap space. This guest-level swap space must be greater than or equal to the difference between the virtual machine’s
configured memory size and its Reservation.
o Many workloads present opportunities for sharing memory across virtual machines.
o To determine the effectiveness of memory sharing use resxtop or esxtop to observe the actual savings. The PSHARE field of the interactive
mode in the Memory page.
o You measure guest physical memory using the Memory Granted metric (for a virtual machine) or Memory Shared (for an ESX/ESXi host). To
measure machine memory, however, use Memory Consumed (for a virtual machine) or Memory Shared Common (for an ESX/ESXi host).
o The VMkernel maps guest physical memory to machine memory.
o Multiple regions of guest physical memory might be mapped to the same region of machine memory (in the case of memory sharing) or
specific regions of guest physical memory might not be mapped to machine memory (when the VMkernel swaps out or balloons guest physical
memory) VCP-410 dumps
o Resource Pool Hierarchy can have Parents, Children, and Siblings.
o Resource Pool Admission Control - Before you power on a virtual machine or create a resource pool, check the CPU Unreserved and Memory
Unreserved fields in the resource pool’s Resource Allocation tab to determine whether sufficient resources are available.
o A group power on will power on multiple virtual machines at the same time.
o VMotion does not support raw disks or migration of applications clustered using Microsoft Cluster Service (MSCS).
o Other VMware products or features, such as VMware vApp and VMware Fault Tolerance, might override the automation levels of virtual
machines in a DRS cluster.
o An affinity rule specifies that two or more virtual machines be placed on the same host. An anti-affinity DRS rule is limited to two virtual
machines,
o If two rules conflict, the older one will take precedence, and the newer rule is disabled.
o Disabled rules are ignored. DRS gives higher precedence to preventing violations of anti-affinity rules than violations of affinity rules.
o When a host machine is placed in standby mode, it is powered off.
o Hosts are placed in standby mode by the VMware DPM feature
o A cluster becomes overcommitted (yellow) when the cluster does not have the capacity to support all resources reserved by the child resource
pools. Typically this happens when cluster capacity is suddenly reduced.
o A cluster enabled for DRS becomes invalid (red) when the tree is no longer internally consistent, that is, resource constraints are not observed.
o VMware DPM can use one of three power management protocols
o IPMI - Intelligent Platform Management Interface
o iLO - Hewlett-Packard Integrated Lights-Out
o WOL - Wake-On-LAN
o If a host supports multiple protocols, they are used in the following order: IPMI, iLO, WOL.
o The VMotion NIC on each host must support WOL to use that protocol.
o The DRS threshold and the VMware DPM threshold are essentially independent. You can differentiate the aggressiveness of the migration and
host-power-state recommendations.
o Verify that DPM is functioning properly by viewing each host’s Last Time Exited Standby information.
o The most serious potential error you face when using VMware DPM is the failure of a host to exit standby mode when its capacity is needed
by the DRS cluster. Use the preconfigured Exit Standby Error alarm for this error.
o DRS Recommendations have 5 levels (1-5). Priority 1, the highest, indicates a mandatory move because of a host entering maintenance or Passed VCP-410
standby mode or DRS rule violations. Other priority ratings denote how much the recommendation would improve the cluster’s performance;
o Prior to ESX/ESXi 4.0, recommendations received a star rating (1 to 5 stars) instead of a priority level.
o Non-Uniform Memory Access (NUMA) systems are advanced server platforms with more than one system bus.
o Some virtual machines are not managed by the ESX/ESXi NUMA scheduler: if you manually set the processor affinity for a virtual machine, or
virtual machines that have more virtual processors than the number of physical processor cores available on a single hardware node.
o When a virtual machine is powered on, ESX/ESXi assigns it a home node. This is initially assigned to home nodes in a round robin fashion.

o Perform a rescan each time you make one of the following changes:
o Create new LUNs on a SAN.
o Change the path masking on a host.
o Reconnect a cable.
o Make a change to a host in a cluster.
o Change CHAP settings or add new discovery addresses.
o If you notice unsatisfactory performance for your software iSCSI LUNs, you can change their maximum queue depth by using the vicfgmodule
command. VCP-410 exam
o The iscsi_max_lun_queue parameter is used to set the maximum outstanding commands, or queue depth, for each LUN accessed through the
software iSCSI adapter. The default is 32, and the valid range is 1 to 255.
o Setting the queue depth higher than the default can decrease the total number of LUNs supported.
Appendix A - iSCSI SAN Configuration Checklist
o Set the following Advanced Settings for the ESX/ESXi host:
o Set Disk.UseLunReset to 1
o Set Disk.UseDeviceReset to 0
Appendix B - VMware vSphere Command-Line Interface
o The resxtop command provides a detailed look at ESX/ESXi resource use in real time.
o The vicfg-iscsi command allows you to configure software or hardware iSCSI on ESX/ESXi hosts, set up CHAP parameters, and set up
iSCSI networking.
o Use the vicfg-mpath command to view information about storage devices, paths, and multipathing plugins.
o Use the esxcli corestorage claimrule command to manage claim rules. Claim rules determine which multipathing module should
claim paths to a particular device and manage the device.
o The vmkping command allows you to verify the VMkernel networking configuration.
Appendix C - Managing Storage Paths and Multipathing Plugins (Same as Appendix B in the Fibre Channel SAN Configuration Guide)
Resource Management Guide
o The need for resource management arises from the over-commitment of resources.
o Resources include CPU, memory, power, storage, and network resources.
o The guide focuses primarily on CPU and memory. Power resource consumption can also be reduced with the Distributed Power Management
(DPM) feature.
o ESX/ESXi manages network bandwidth and disk resources on a per-host basis, using network traffic shaping and a proportional share
mechanism, respectively. VCP-410 exam questions
o Shares specify the relative priority or importance of a virtual machine (or resource pool).
o Shares are typically specified as High, Normal, or Low and these values specify share values with a 4:2:1 ratio. (or can set Custom value)
o A reservation specifies the guaranteed minimum allocation for a virtual machine.
o The reservation is expressed in concrete units (megahertz or megabytes).
o Reservation defaults to 0.
o Limit specifies an upper bound for CPU or memory resources that can be allocated to a virtual machine. It never gets more than this.
o A limit is expressed in concrete units (megahertz or megabytes).
o CPU and memory limit default is unlimited.
o Using limits can be beneficial if you want to manage user expectations, but might waste idle resources.
o Expandable Reservation defines whether reservations are considered during admission control.
o Overhead Reservation is the amount of the “Reserved Capacity” field that is being reserved for virtualization overhead.
o Worst Case Allocation is the amount of (CPU or memory) resource that is allocated to the virtual machine based on user-configured resource
allocation policies (for example, reservation, shares and limit), and with the assumption that all virtual machines in the cluster consume their
full amount of allocated resources.
o Admission Control - If enough unreserved CPU and memory are available, or if there is no reservation, the virtual machine is powered on.
Otherwise, an Insufficient Resources warning appears.
o ESX/ESXi cannot enable hyperthreading on a system with more than 32 physical cores, because ESX/ESXi has a logical limit of 64 CPUs.
o Hyperthreaded Core Sharing Modes:
o Any - can freely share cores with other virtual CPUs.
o None - each virtual CPU should always get a whole core to itself, with the other logical CPU on that core being placed into the halted
state. VCP-410 study guide
o Internal - cannot share cores with vCPUs from other virtual machines. Can share cores with the other virtual CPUs from the same virtual
machine. Only for SMP virtual machines.
o For the best performance, when you use manual affinity settings, include at least one additional physical CPU in the affinity setting to allow at
least one of the virtual machine’s threads to be scheduled at the same time as its virtual CPUs.
o Dynamic Voltage and Frequency Scaling (DVFS) - You can configure your hosts to dynamically switch CPU frequencies based on workload
demands.

o On ESXi, it is not possible to rescan a single storage adapter.
o You can modify the Disk.MaxLUN parameter to improve LUN discovery speed.
o You cannot discover LUNs with a LUN ID number that is greater than 255.
o You can disable the default sparse LUN support to decrease the time ESX/ESXi needs to scan for LUNs.
o The sparse LUN support enables the VMkernel to perform uninterrupted LUN scanning when a storage system presents LUNs with VCP-410 dumps
nonsequential LUN numbering.
o NPIV enables a single FC HBA port to register several unique WWNs with the fabric, each of which can be assigned to an individual virtual
machine.
o The virtual machine’s configuration file (.vmx) is updated to include a WWN pair (consisting of a World Wide Port Name and a World Wide
Node Name).
o If NPIV is enabled, four WWN pairs (WWPN & WWNN) are specified for each virtual machine at creation time. All physical paths must be
zoned to the virtual machine.
o NPIV can only be used for virtual machines with RDM disks. Physical HBAs, must have access to all LUNs that are to be accessed by virtual
machines running on that host.
o By default, the host performs a periodic path evaluation every 5 minutes causing any unclaimed paths to be claimed by the appropriate MPP.
o Make sure read/write caching is enabled.
o Dynamic load balancing is not currently supported with ESX/ESXi.
o Path thrashing only occurs on active-passive arrays
Appendix A – Multipathing Checklist
Appendix B – Managing Storage Paths and Multipathing Plugins
o Claim rules indicate which multipathing plugin, the NMP (Native MP) or any third-party MPP, manages a given physical path.
o List claim rules esxcli corestorage claimrule list
o To list all multipathing modules: vicfg-mpath –server –list-plugins
o List all VMware SATPs: esxcli nmp satp list
o List all storage devices: esxcli nmp device list
iSCSI SAN Configuration Guide
o There is no mention of requiring a Service Console connection for iSCSI anymore.
o Virtual SCSI controllers - BusLogic Parallel, LSI Logic Parallel, LSI Logic SAS, and VMware Paravirtual.
o iSCSI Name identifies a particular iSCSI element. The iSCSI name can use either IQN or EUI format.
o IQN (iSCSI qualified name) - can be up to 255 characters long and has the following format: iqn.yyyy-mm.naming-authority:unique_name VCP-410
o EUI (extended unique identifier) - takes the form eui.
o iSCSI aliases - not unique, and are intended to be just a friendly name to associate with the node.
o You must enable your software iSCSI initiator so that ESX can use it to access iSCSI storage.
o Dynamic Discovery - Also known as Send Targets discovery responds by supplying a list of available targets to the initiator. The names and IP
addresses of these targets appear on the Static Discovery tab. If you remove a static target added by dynamic discovery, the target might be
returned to the list the next time a rescan happens, the HBA is reset, or the host is rebooted.
o Static Discovery - The initiator does not have to perform any discovery.
o Dynamic discovery obtains a list of accessible targets from the iSCSI storage system, while static discovery can only try to access one particular
target by target name.
o You cannot change the IP address, DNS name, or port number of an existing Send Targets server. To make changes, delete the existing server
and add a new one.
o To protect the integrity of iSCSI headers and data, the iSCSI protocol defines error correction methods known as header digests and data
digests. Both parameters are disabled by default, but you can enable them.
o Check the end-to-end, noncryptographic data integrity beyond the integrity checks that other networking layers provide.
o Enabling header and data digests does require additional processing for both the initiator and the target. Intel Nehalem processors offload
the iSCSI digest calculations.
o Use the esxcli command to connect the VMkernel ports to the software iSCSI initiator.
o Jumbo Frames up to 9kB (9000 Bytes) are supported.
o You cannot change the IP address, DNS name, iSCSI target name, or port number of an existing target. To make changes, remove the existing
target and add a new one. VCP-410 braindump
o iSCSI requires that all devices on the network implement Challenge Handshake Authentication Protocol (CHAP), which verifies the legitimacy
of initiators that access targets on the network. (EDIT - I don’t think its “required”)
o ESX/ESXi supports one-way CHAP for both hardware and software iSCSI, and mutual CHAP for software iSCSI only.
o For software iSCSI only, you can set one-way CHAP and mutual CHAP for each initiator or at the target level.
o Hardware iSCSI supports CHAP only at the initiator level.
o For software iSCSI, the CHAP name should not exceed 511 and the CHAP secret 255 alphanumeric characters.
o For hardware iSCSI, the CHAP name should not exceed 255 and the CHAP secret 100 alphanumeric characters.
o Boot from a SAN - ensure that the LUN is presented to the ESX system as LUN 0. The host can also boot from LUN 255.

Appendix A – ESX Technical Support Commands
Command Purpose
esxcfg-advcfg advanced options
esxcfg-auth Configures authentication
esxcfg-boot bootstrap settings
esxcfg-dumppart Configures a diagnostic partition
esxcfg-firewall service console firewall ports
esxcfg-info Information about the state of the service console, VMkernel, various subsystems in the virtual network, and
storage resource hardware. VCP-410 exam questions
esxcfg-init Internal initialization routines. Used for the bootstrap process you should not use it under any circumstances.
esxcfg-module Sets driver parameters and modifies which drivers are loaded during startup.
esxcfg-mpath multipath settings for your Fibre Channel or iSCSI disks.
esxcfg-nas Manages NFS mounts
esxcfg-nics physical network adapters
esxcfg-resgrp resource group settings
esxcfg-route default VMkernel gateway route
esxcfg-swiscsi software iSCSI software adapter.
esxcfg-upgrade Upgrades from ESX Server 2.x to ESX.
esxcfg- scsidevs Prints a map of VMkernel storage devices to service console devices.
esxcfg-vmknic VMkernel TCP/IP settings for VMotion, NAS, and iSCSI.
esxcfg-vswif service console network settings.
esxcfg-vswitch virtual machine network settings.
Appendix B – Linux Commands Used with ESX
Appendix C – Using vmkfstools
o vmkfstools utility is used to create and manipulate virtual disks, file systems, logical volumes, and physical storage devices.
Fibre Channel SAN Configuration Guide
o Zones define which HBAs can connect to which SPs.
o Zoning is similar to LUN masking, which is commonly used for permission management. Usually, LUN masking is performed at the SP or server
level.
o WWPN (World Wide Port Name) is a globally unique identifier for a port.
o Port ID (or port address) enables routing. FC switches assign the port ID when the device logs in to the fabric.
o When N-Port ID Virtualization (NPIV) is used, a single FC HBA port (N-port) can register with the fabric by using several WWPNs.
o active-active - access to the LUNs simultaneously through all the storage ports that are available, without significant performance degradation. VCP-410 study guide
o active-passive - one port is actively providing access to a given LUN. The other ports act as backup
o Disk shares are relevant only within a given ESX/ESXi host.
o Virtual machine I/O might be delayed for up to sixty seconds while path failover takes place. I/O delays might be longer on active-passive
arrays.
o On virtual machines running Microsoft Windows, increase the value of the SCSI TimeoutValue parameter to 60.
o Only one VMFS volume per LUN.
o Unless you are using diskless servers, do not set up the diagnostic partition on a SAN LUN.
o ESX/ESXi does not support FC connected tape devices.
o You cannot use virtual machine logical-volume manager software to mirror virtual disks. Dynamic disks on a Microsoft Windows virtual
machine are an exception, but require special configuration.
o You should not mix FC HBAs from different vendors in a single server.
o Use a dedicated SCSI adapter for any tape drives that you are connecting to an ESX/ESXi system.
o You should not use boot from SAN in the following situations:
o If you are using Microsoft Cluster Service.
o If I/O contention might occur between the service console and VMkernel.
o Proper LUN masking is critical in boot from SAN mode.
o Runtime Name - the name of the first path to the device. Created by the host. Is not a reliable identifier for the device, and is not persistent.
o vmhba#:C#:T#:L#, where: VCP-410 questions
o vmhba# is the name of the storage adapter
o C# is the storage channel number.
o T# is the target number.
o L# is the LUN number
o If a target has only one LUN, the LUN number is always zero (0).