VCP3

From vwiki
Jump to navigation Jump to search
The printable version is no longer supported and may have rendering errors. Please update your browser bookmarks and please use the default browser print function instead.

{{#widget:Widget:GoogleAdSenseSkyscraper}} 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