System Administration

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System Administration

• Chapter 14

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Objectives

• Describe system administration responsibilities
  and tasks
• Explain the process of acquiring computer
  hardware and system software
• Describe tools and processes for evaluating
  application resource requirements and computer
  system performance
• Define a system security model and describe how
  it can be implemented
• Understand issues related to installing and
  protecting computer hardware

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Chapter Topics
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System Administration

• System Administration responsibilities
• Acquiring new IS resources
• Maintaining existing IS resources
• Designing and implementing an IS security policy
• Ensure the efficient and reliable delivery of
  information services

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System Administration

• Strategic Planning issues
• Strategies for developing services and markets
  for them
• Strategies for acquiring sufficient resources for
  operations and growth
• Organizational structure and control

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System Administration

• Hardware and Software as Infrastructure
• Capital resources have the following
  characteristics
• Service to a large and diverse set of users
• Costs that are difficult to allocate to
  individual users
• Recurring need for new capital expenditures
• Significant operating costs for maintenance

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System Administration

• Hardware and Software as Infrastructure
• The strategic issues that must be addressed by
  organizations are
• What services will be provided?
• How will service users be charged?
• What infrastructure is required to provide the
  services?
• How can the infrastructure be operated,
  maintained, and improved at minimal cost?

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System Administration

• Standards
• Providing infrastructure-based services to a wide
  variety of users requires adopting services
  standards.
• Standardization causes problems for users that
  want services near the leading edge.
• It is hard to standardize when dealing with
  hardware and software.

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System Administration

• Competitive Advantage
• Describes a state of affairs in which one
  organization employs resources so as to give it a
  significant advantage over its competitors.

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System Administration

• Competitive Advantage
• Providing services that competitors are unable to
  provide
• Providing services of unusually high quality
• Providing services at unusually low price
• Generating services at unusually low cost

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The Acquisition Process

• Determine the applications that the
  hardware/software will support.
• Specify detailed requirements in terms of
  hardware and software capability and capacity.
• Draft a request for proposals and circulate it to
  potential vendors.
• Evaluate the responses to the request for
  proposals.
• Contract with a vendor or vendors for purchase,
  installation, and/or maintenance.

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The Acquisition Process

• Determining and Stating Requirements
• Integration with existing hardware/software
• Availability of maintenance services
• Availability of training
• Physical parameters such as size, cooling
  requirements, and disk space for system software
• Availability of upgrades

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The Acquisition Process

• Request for Proposal (RFP)
• A formal document sent to vendors that states
  requirements and solicits proposals to meet those
  requirements.

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The Acquisition Process

• Evaluating Proposals
• Determine acceptability of each proposal
• Rank acceptable proposals
• Validate high-ranking proposals

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Determining Requirements and Evaluating
Performance

• Determining hardware requirements for software
  is difficult
• Computer systems are complex combinations of
  interdependent components.
• The configuration of operating and other system
  software can significantly affect raw hardware
  performance.
• The hardware and system software resources
  required by applications cannot always be
  predicted precisely.

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Determining Requirements and Evaluating
Performance

• Estimating computer requirements
• Application demand model
• Resource availability model

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Determining Requirements and Evaluating
Performance

• Benchmarks
• Select the benchmark test most relevant to the
  intended application.
• Determine the relationship between benchmark
  tests and the actual work that the new computer
  system will perform.

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Determining Requirements and Evaluating
Performance

• Measuring Resource Demand and Utilization
• Hardware monitors
• Software monitors
• Program profilers

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Technology Focus
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Technology Focus
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Security

• Well integrated approach includes measures to
• Protect physical resources against accidental
  loss or damage
• Protect data and software resources against
  accidental loss or damage
• Protect all resources against malicious tampering
• Protect sensitive software and data resources
  against unauthorized access and accidental
  disclosure

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Security

• Access Control Processes
• Authentication the process of determining or
  verifying the identity of a user or process
  owner.
• Authorization - determining whether an
  authenticated user or process has sufficient
  rights to access a particular resource.

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Security
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Security

• Password Controls and Security Methods
• Restrictions on the length and composition of
  valid passwords
• Requirements that passwords periodically be
  changed
• Analysis of password content to passwords that
  are easily guessed
• Encryption of passwords in files and during
  transmission over a network

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Security
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Security
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Security

• Auditing the process of creating and managing
  records of user activity or resource access.

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Security

• Virus Protection Software Capabilities
• Scanning e-mail messages and attachments
• Monitoring access to important system files and
  data structures
• Scanning removable media
• Periodically scanning the file system

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Security

• Software Updates

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Security
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Security
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Security

• Firewalls
• Application firewalls (proxy server) a server
  that handles the service requests of external
  users.
• Stateful firewalls tracks the progress of
  complex client-server interactions.

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Security
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Physical Environment

• Computer Hardware Installation Issues
• Electrical Power
• Heat Dissipation
• Moisture
• Cable Routing
• Fire Protection

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Physical Environment

• Electrical Power - fluctuations in power can
  cause
• Momentary power surges
• Momentary power sags
• Long-term voltage sags
• Total loss of power

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Physical Environment

• Heat Dissipation
• All computer equipment requires some means of
  heat dissipation.
• Many hardware devices use fans to move air
  through the unit.
• Auxiliary cooling can be provided within an
  individual equipment cabinet.

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Physical Environment

• Moisture
• Excessive moisture is an enemy of electrical
  circuitry.
• Well-designed cabinets are one defense against
  the dangers of moisture.
• Humidity can be controlled automatically by
  optional components of heating, ventilation and
  air conditioning systems.

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Physical Environment

• Cable Routing
• A raised floor is generally used in a room that
  contains multiple hardware cabinets, a single
  mainframe computer system or multiple
  minicomputers.

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Physical Environment

• Fire Protection
• Carbon dioxide, fire retardant foams and powders,
  and various gaseous compounds are alternate
  methods of fire protection, but not for computer
  equipment.
• Halon gas is used around computer equipment since
  is does not promote condensation.

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Physical Environment

• Disaster Planning and Recovery
• Periodic data backup and storage of backups at
  alternate sites.
• Backup and storage of critical software at
  alternate sites.
• Installing of duplicate or supplementary
  equipment at alternate sites.
• Arrangements for leasing existing equipment at
  alternate sites, such as with another company or
  a service bureau.

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Summary

• The primary responsibility of a system
  administrator is to ensure efficient and reliable
  delivery of IS services.
• IS resource acquisition and deployment should
  occur only in the context of a well-defined
  strategic plan for the organization as a whole.
• Providing infrastructure-based services to a wide
  variety of users requires the adoption of service
  standards.

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Summary

• Planning for IS resource acquisition requires a
  thorough understanding of present and anticipated
  needs.
• Determining hardware requirements is one of the
  most difficult system administration tasks.
• Computer hardware and software performance
  evaluation and requirements determination can be
  performed with mathematical models.

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Summary

• Computational approaches applicable to computer
  performance and application requirements modeling
  are of two types static and dynamic.
• Automated tool such as hardware monitors,
  software monitors and program profilers are
  available to measure resource demand and
  utilization.

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Summary

• The information processing resources of many
  organizations represent a sizable investment.
• The installation of computer hardware requires
  special attention to many aspects of its physical
  environment.