Workstation Imaging

1
Workstation Imaging

• for
• Student Networks
• using
• Novell Zenworks 3.2
• Novell Netware 6.0
• Monash University
• 2003

2
Presentation Overview

• This presentation is divided into three major
  parts
• 1. Network Deployment Methodology
• Current network environment at Monash
• Broadcast, Multicast and Snooping
• 2. Workstation Disk Image Management
• Contents of Disk Images
• NDS containers and objects
• Zenworks scripting
• 3. Future Developments

3
Part1 Network Deployment

• Current Network Environment at Monash
• What has changed
• What is changing
• Broadcast and Multicast
• Multicast Snooping
• Delployment Basics
• Typical Lab

4
Changed Network Environment

• Netware 4 and IPX on the way out
• Netware 6 and IP only networking
• Novell Zenworks 3.2 sp1 with
• Zenworks Image Deployment with scripting
• Remote Boot PXE option
• Wake On LAN
• Remote Control options
• Workstation Inventory Database

5
Opportunities

• IPX could only broadcast disk images
• Everybody suffered
• IP allows multicast
• Network not configured to differentiate between
  broadcast and multicast
• All mass deployment tools have multicast
• Integration of workstation management tools
  through Zenworks
• deployment, remote control, inventory, etc.

6
Network Enhancements

• Micros and NIS have been testing two new
  services to enhance delivery of disk images.
• Multicast Snooping
• To prevent the multicast of a disk image to
  deluge all ports on a subnet in the same way a
  broadcast does
• Proxy-DHCP via IP Helper Address
• To forward requests for remote boot information

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Why Multicast Snooping?

• Multicast is designed for routed networks
• Workstations join a multicast group dynamically
  managed by the router
• The router only forwards the multicast traffic to
  the subnets where there are workstations that
  joined the group
• All workstations on a subnet see the multicast as
  broadcast traffic
• Ethernet switches normally ignore multicasts
• Ethernet switches associate an address with a
  port
• Deliver traffic addressed to a workstation only
  on the port it is connected to
• Broadcasts and Multicast are delivered to all
  ports because the switch does not know which
  workstations really need it

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Multicast Snooping On

• The ethernet switch monitors which stations have
  joined a multicast group
• Multicasts for the group are only sent to the
  switch ports where a workstation has joined
• Ports where no workstation joined are not deluged
  with the multicast traffic
• Users on the same switch port will still get all
  the traffic

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Multicast Snooping at Monash

• Currently there is not a great deal of experience
  at Monash with multicast snooping (expect
  refinements).
• Multicast sessions across multiple ports
  occasionally drop out.
• No reduction in core network bandwidth usage.
• Certainly prevents multicast sessions from
  flooding adjacent ports.
• Best used within a single port of 10 shared 10
  ways (hub attached to a switch port)

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Typical Lab Setup

• Typical lab has 3 strings of workstations
  attached to hubs
• Each hub less than ten workstations
• Unicast to one workstation on each of the switch
  ports
• Multicast from each of the unicast receivers to
  all of the workstations on the same port
• No multicast across switch ports

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Unicast from Server to Masters
Image Server
Script from the server deletes all partitions
except Zenworks, downloads Linux, creates NTFS
partition for windows (XP or 2K), then downloads
syspreped windows files.
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Multicast from Masters to Clients
Image Server
Script from server initiates multicast session
from fully prepared workstations to the remainder
on the same switch port. At completion each
station reboots and the syspreped windows images
do a self install.
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Part 2 Workstation Images

• Image Delivery Steps
• Image Structure on Workstation Disk
• Imaging Operations
• Workstation Registration
• NDS Containers and Objects

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Image Delivery Steps

• Install Zen Imaging Partition
• Boot from CD or floppies and select install
  option (this wipes all other disk partitions and
  data)
• Server based rules select image script
• IP Addresses (as entered in Addhost)
• Zenproxy configuration
• Disk Size
• Must match the motherboard
• Script can contain many commands
• Repartition remainder of disk
• Download Linux and/or Windows image(s)
• Make local copy
• Join a multicast session

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Workstation Disk Image Structure

• Workstation Disk

Partition Layout P0 Zenworks Imaging
50Mb small, 4Gb large (can hold compressed
images) P1 Linux Monolithic (optional) 3Gb self
contained image P2 Windows NTFS 4Gb minimum
size, to remainder of disk Starts before cylinder
1024 Use P1 if no Linux
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Zenworks Imaging Partition
Install Zenworks Imaging Partition Choose size
of partition based on the size of the disk.
Either 50Mb or 4Gb Zen partition. To hold a
compressed image of Windows or Linux about 1-2Gb
is required. Smallest Zenworks partition to hold
images will be about 4Gb. Since smallest Linux is
3Gb and Windows is 4Gb, the smallest disk to hold
local images is 11Gb. Anything smaller than that
must be refreshed from the server and will have a
50Mb Zen partition. Configuration on disk
specifies a Zenproxy server from which the
workstation will extract its imaging instructions.

Zen CD
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Standard Imaging Operations

Initial Workstation OS Delivery via the
Network Delivers disk image to workstation from
the imaging server(s). (40 60 minutes) This
operation delivers desired combination of disk
partitions according to the imaging script which
must be compatible with the hardware. LINUX12.ZMG
encompasses known purchases WIN2K-06.ZMG base
image that suits most P3s Addon Images for
CompaQ, Intel, MicroPro, HP VL400, etc.
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Standard Imaging Operations

Local Save of Windows Image Compresses disk
partition image of Windows and stores it on the
Zenworks partition as a file. (10 to 15 minutes)
This operation makes it possible to save the
completely setup and installed operating system
and local applications ready for quick
restoration if corruption occurs. (see next slide)
19
Standard Imaging Operations

Local Restore of Windows Image Decompresses disk
partition image of Windows on the Zenworks
partition and writes it to the NTFS partition.
(10 to 15 minutes) This operation makes it
possible to restore the previously completed
setup and installed operating system with all
local applications ready for use.
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Standard Imaging Operations

Multicast Master Delivers whole disk image of
multiple partitions to other identical
workstations. This operation sends out current
combination of disk partitions to workstations
set up by their scripts to be multicast clients
with the same session name. Master
21
Workstation Registration

• First run of Linux does a self configure
• If workstation is in Addhost
• Updates delivered by configuration server
• First run of Windows runs Setup
• Loads and configures device drivers
• Establishes IP address and DNS name
• Registers workstation object in NDS

22
NDS Containers and Objects

• NDS Tree has containers for each distinct
  management group
• Container names conform to well known
  abbreviations use in DNS
• ConsoleOne is the tool for managing workstation
  images and image scripts

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NDS Containers and Objects

• Within each Faculty/Division there is a set of
  standard objects and containers
• Two containers for specific imaging objects and
  operations
• Imaging scripts are held in the image container
• Workstations, Workstation Groups and Policies are
  held in the workstation container
• Two roles with different rights
• Image-managers
• Workstation-managers
• Directory Map object to denote location of image
  files.

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Image Objects

• Scripts to carry out operations
• Managed by Image-Managers Role
• Sample Scripts
• Create Partitions
• Download Dual Boot Linux/Windows
• Local Save
• Local Restore

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Workstation Objects

• Workstations and Workstation Groups and managed
  by Workstation-Manager role.
• Login as Local Administrator
• Profile not deleted on logout
• Associate applications to workstation groups
• Workstation Policies are managed by the
  Policy-Manager role.
• Assign printers
• Set Client Configuration

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Part 3 Future Developments

• Not all services are currently implemented
• Remote Boot PXE
• Workstation Inventory
• Removal of Netware Client

27
Remote Boot PXE

• PXE stands for Preboot eXecution Environment
• PXE is the IP version of remote boot
• Works across routers
• Requires Proxy-DHCP and TFTP servers
• Monash trial implementation used router IP Helper
  address (expect improvements before production)
• Can allow all Zenworks imaging operations
• Without Zenworks partition on the workstation
• Requires rules (IP address, Disk size) to select
  image if workstation not in NDS.

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Workstation Inventory

• Plans drawn up
• No implementation schedule

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Netware Client Removal

• This feature coming with Zenworks 4

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Further Information

• Help within ConsoleOne
• Novell Website access

31
Workstation Management

• for
• Student Networks
• using
• Novell Zenworks
• Monash University
• 2003