VCP3

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

Other Resources

• VI3 Online Manual - useful for searches
• VI3 Documentation - recommend downloading entire set for reference, anything that's in these docs is fair game to be examined on
  • See the "Main Documentation Set"
  • Configuration Maximums - must read/learn the key numbers
• VI3 Exam Blueprint (i.e. the syllabus)
• VI3 Reference Card - very condensed reference manual

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