VCP3

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These are my notes, which covers holes in my knowledge, there is likely to be holes in your knowledge not covered here!

Other Resources

Exam Overview

  • VCP-310
  • 75 multi-choice questions in 105 mins
  • The exam gets updated with every new major software version, eg its now current for ESX v3.5 / SC v2.5

Exam Crib Notes

Random notes in italics came up in exam but aren't actually covered in notes

VMware Products

  • Lab Manager - Manages a VM image library, eg for use in development teams
  • Site Recovery Manager - Manages and automates disaster recovery plant for a Virtual Infrastructure
  • Virtual Desktop Infrastructure (VDI) - Desktops hosted as VM's (like a full fat equivalent of Citrix)
  • VMware Workstation - Runs VMware on a desktop/laptop (salesmen demos, developers, etc)
  • VMware Server - The free alternative to ESX server
    • Runs on top of Win or Unix host OS (inc 64bit)
    • Supports 2 vCPU's per VM (max)
    • No VLAN support in vSwitches


ESX Server

Minimum Supported Spec

  • Dual 1.5GHz CPU
  • 1 GB RAM
  • 1x NIC
  • Storage

ESX Installation

Required disk partitions;

  • /boot
  • swap
  • /
  • VMFS - Required for VM files, local VMFS should not be created by installer as won't 64k aligned (may cause performance probs)
  • vmkcore - Require for PSOD dumps

During ESX install, selecting Create default network for virtual machines... causes VM's to share vSwitch with Service Console

Key components

  • Virtualisation layer (inc VMM)
  • Hardware interface components
  • User interface (VC/VI Client access, etc)

vSwitch Traffic Shaping

  • Affects outgoing traffic only
  • Per virtual port
  • Configured at vSwitch or Port Group level

Possible config parameters;

  • Average Bandwidth - KB/s - Allowed average load
  • Burst Size - KB - Maximum size of a burst
  • Peak Bandwidth - KB/s - Absolute max during a burst, after which traffic is restricted to Average Bandwitdh

Other stuff;

  • TSO enabled by default
  • Jumbo frames must be enabled via command line

SAN

Multipath recommendations;

  • For Active/Passive use Most Recently Used
  • For Active/Active use Fixed (but doesn't really matter)

Need to know about Round-Robin as well

LUN Addressing;

  • Adapter : Target(SAN's SP) : LUN ID : Partition ID
  • EG vmhba1:1:0:1

Benefits of Boot from SAN

  • Cheaper servers
  • Easier server replacement
  • Less wasted space
  • Easier backup process (SAN image can be backed up)
  • Improved management

Don't boot from SAN if

  1. Using MS Cluster Services (not compatible)
  2. I/O contention might occur between Service Console and VMkernel

SAN Zoning effects

  • Reduces the number of targets and LUN's presented to an ESX
  • Controls and isolates paths in a fabric
  • Can prevent non-ESX systems from seeing VI/ESX storage
  • Can be used to separate environments (eg Production and Development)


iSCSI

iSCSI TCP port used (Default port is TCP3260, TCP860 can also be used but must be explicitly specified)

  • Software - Requires VMKernel and Service Console to be able to see iSCSI target
  • Hardware - Requires iSCSI HBA card, allows ESX to boot from SAN if required

Initiator connects to an iSCSI name, one of

  • iSCSI Qualified Name (IQN) - Commonly used, format of IQN.YYYY-MM.NameAuthority:UniqueName
  • Enterprise Unique Identifier (EUI) - Not so common, format of EUI.<16 Hex digits>

Modes of iSCSI target discovery;

  • Dynamic Discovery - Finds all available targets/names on iSCSI host (uses SendTargets command)
  • Static Discovery - Connect to a specific name
  • CHAP Authentication
    • Optional, not enabled by default
    • Same set of credential's for all iSCSI connections
    • Unidirectional only

Virtual Centre

Requirements

Hardware

  • 2 GHz CPU
  • 2 GB RAM
  • 560 MB disk (2GB recommended)

Software

  • Windows OS (32 bit only)
    • Win2k SP4 + rollup patches
    • WinXP Pro SP2
    • Win 2k3 SP1 or R2
  • IE 5.5 or higher
  • Database
    • MS SQL 2k SP4 or 2k5
    • Oracle 9I or 10G

Core Services

  • Host and VM configuration
  • VM provisioning
  • Alarms and event managment
  • Statistics logging
  • Task scheduler
  • Resources and VM inventory managment
  • Consolidation

Interfaces

  • Active directory interface
  • Database interface
  • VI API
  • ESX server managment


Virtual Machines

  • VMware recommend separate VMDK's for OS and App/data drives
  • Hit ESC at startup to enter BIOS boot order menu
  • To enable TSO or Jumbo frames support, replace NIC driver with Enhanced vmxnet, then upgrade VMTools

SCSI Bus Sharing

  • None - Default, VMDK is dedicated to VM
  • Virtual - VMDK is shared by VM's on same ESX
  • Physical - Direct access to LUN, can be shared by any VM
    • If using RDM use physical

Snapshots

  • Snapshot is a record of VM's state (memory, config settings, disk)
  • During snapshot, all VM activity is paused

HD Independence

  • Persistent - Changes are written straight to VMFS disk
  • Non Persistent - Changes are discarded at VM power off

VMotion

  • VM's VMDK's must be on shared storage (inc NFS/NAS)
  • Host's CPU's must be same model family (and so also same make)
  • Speed and cache size do not have to match
  • Extended features probably do need to match (eg SSE or NX)


User Access Roles

Default, out-of-the-box roles settings;

  • No Access - System role (can't be edited)
  • Read Only - System role (can't be edited)
  • Administrator - System role (can't be edited)
  • Virtual Machine User - Basic day 2 day VM operations, nothing CMF worthy
  • Virtual Machine Power User - Additionally, add/remove/change VM's devices
  • Resource Pool Administrator - Additionally, config resources and pools, config VM alarms
  • Datacentre Administrator - Host and datacenter, alarms, limited VM access
  • Virtual Machine Administrator - Full access, except can't; change user permissions, tasks, update manager

Resource Management

Covered heavily in exam - know about the effects of CPU affinities on Resource Pool limits and VM reservations etc

  • CPU & Memory - Managed at the Cluster/Resource Pool level
  • Disk & Network - Managed by the ESX
  • Default share weightings: High : Normal : Low = 4 : 2 : 1

Settings

  • Configured Size - Amount the VM believes it has
  • Shares - Contention priority for resource is more than Reservation is available
  • Reservation - Guaranteed lower bound of resource
  • Limit - Upper bound of physical usage (generally equal to Configured Size)

Resource Pool Benefits

  • Flexible hierarchical organisation
  • Isolation between pools, sharing within them
  • Access control, administrative delegation
  • Separation of resources from hardware
  • Management of sets of VM's running multi-tier services (on the same shared physical infrastructure)

Resource Pool Admission Control

  • Fixed Reservation - Resources must be available in VM's resource pool to allow power on
  • Expandable Reservation - Resources must be available in VM's resource pool or parent resource pools, to allow power on

Advanced Config Settings

  • Mem.BalancePeriod - Interval for automatic memory reallocation (default = 15 secs)
  • Mem.SamplePeriod - Interval for VM working set memory monitoring (default = 60 secs)
  • Mem.IdleTax - Makes idle VM memory cost more than used memory (default = 75%)
  • Mem.ShareScanTime - Time for a VM to be scanned for page sharing opportunities (default = 60 mins)

HA & DRS

  • HA cluster has 5 primary hosts, any more are secondary. Therefore can handle 4 simultaneous failures.
  • 32 hosts max per cluster

VMware Consolidated Backup

Benefits of VCB

  • Reduces backup load on ESX's
  • Eliminates need for backup window
  • Simplifies administration
  • Backup VM's regardless of power state

Backup methods

  • Backup agent on VM - Traditional method, backup server can be physical or virtual, if physical then VMware recommend using VCB instead
  • Backup agent in Service Console - Backup server can be physical or virtual, if physical then VMware recommend using VCB instead
    • Power off VM's, then backup entire VMDK file
  • Datastore backup - Using SAN snapshots or NFS backup
  • VCB Windows VM OS - File level backup
  • VCB any VM OS - Full system (VMDK image) backup (no file level available)

VCB Modes

  • LAN
    • VCB proxy can be virtual or physical
    • Accesses ESX over LAN (TCP 902) to backup VM's
  • SAN
    • VCB proxy can be virtual or physical if accessing through iSCSI
    • VCB proxy must be physical if accessing through fibre channel

VCB Workflow

  • Very first backup of VM must be done while VM is powered off
  1. Backup software calls pre-backup script
    1. Runs custom pre-freeze script (optional)
    2. Quiesces NTFS and FAT
    3. Puts VM into snapshot mode
    4. VM is unquiesced (& unfrozen if applicable), returns to normal service
    5. Snapshot is made available to backup software
  2. Backup of snapshot occurs
  3. Backup software call post-backup script
    1. Unmounts snapshot from VCB proxy
    2. Takes VM out of snapshot mode

Consolidation

Need to know this