Network AdministrationNetwork Administration

Summary and the Summary and the Future….Future….

A PhilosophyA Philosophy System Administration is aboutSystem Administration is about

– Putting together a network of computersPutting together a network of computers– Getting them to run some applicationsGetting them to run some applications– Keeping them running in a dynamic worldKeeping them running in a dynamic world

System Administration is as much about System Administration is as much about technology as it is about user behaviourtechnology as it is about user behaviour

System Administration requires constant System Administration requires constant monitoring and rapid response to monitoring and rapid response to problemsproblems

The Next Generation – IPv6The Next Generation – IPv6

IP is the backbone of the network, butIP is the backbone of the network, but– Address Classes waste scarce connectionsAddress Classes waste scarce connections– TCP connections are too easy to disrupt because it TCP connections are too easy to disrupt because it

can be easy to guess sequence#can be easy to guess sequence#– No native support for encryption or mobilityNo native support for encryption or mobility

IPv6IPv6– uses 128-bit addressesuses 128-bit addresses

enough for 10K connections per menough for 10K connections per m22 of the entire planet of the entire planet – Additional headers for encryption, routing & controlAdditional headers for encryption, routing & control– Better support for unicast & multicast, plus anycastBetter support for unicast & multicast, plus anycast

List of what NOT to Do….List of what NOT to Do….Security should be a state of mind!Security should be a state of mind!

Never….Never…. Login as Login as AdministratorAdministrator or or rootroot except for special functions. except for special functions.

Running complex programs as root may lead to virus invasion Running complex programs as root may lead to virus invasion or accidents.or accidents.

Leave a root shell running on system console.Leave a root shell running on system console. Leave root shell running on a public terminal.Leave root shell running on a public terminal. Leave services running that are not used.Leave services running that are not used. Allow physical access to secure equipment.Allow physical access to secure equipment. Make changes that may prevent normal operation after restart. Make changes that may prevent normal operation after restart.

Eg set root shell or password file that is not available at boot.Eg set root shell or password file that is not available at boot. Make undocumented non-reproducible changes. Make undocumented non-reproducible changes.

They may be lost after a system updateThey may be lost after a system update Make quick-fix changes by hand. Better to plan & automate.Make quick-fix changes by hand. Better to plan & automate.

Information Management in the FutureInformation Management in the FutureBurgess, Ch 12.3 Pg 339Burgess, Ch 12.3 Pg 339

“The future is almost upon us and no branch of technology has exploded with such lack of planning and critical review as information technology. The state of our world knowledge is already well beyond our ability to cope with it. We currently have no way of searching and accessing most of the scientific and cultural resources which have been produced in the untold years of human endeavour of our history. In short, in our present state, most of our scientific knowledge has gone to waste. This is clearly an unacceptable situation and it is probably one which will be solved by new information retrieval technology in the future, but the ability to retrieve information is critically dependant on its being organised into an easily parsable structure. This is the basis of programming algorithms in computer software, and the same thing applies to conglomerations of different software systems. The same principle applies to the storage of any kind of information. If information is not organised by a clear principle, it will get lost or muddled.”“Structure and organisation are the unsung heroes of science and society. While scientists and computer hackers are frequently portrayed in the popular press as absent-minded muddlers, subject to fits of divine inspiration, the random elements play only a minor role in the true development of knowledge. Contrary to the popular affectation, it is not cool to have a relaxed attitude to organisation. Claims that systems administration is a “dirty” business, not for academics, that we fly by the seat of our pants and so on, only server to demean the profession. If there is one service we can do for the future, it is to think critically and carefully about the information structures of our network communities.”

Network Administration and Network Administration and System EngineeringSystem Engineering

System designers need admin experienceSystem designers need admin experience When applications are designed to be When applications are designed to be

responsible for own security and intrusion responsible for own security and intrusion detection, the whole system will be detection, the whole system will be reliable and secure. At this time, these reliable and secure. At this time, these functions are imposed by the agents functions are imposed by the agents external to the application, with external to the application, with consequent problems.consequent problems.

““Think Globally, Act Locally!”Think Globally, Act Locally!”

The Future of The Future of System AdministrationSystem Administration

New generations of hardware and software New generations of hardware and software with self-analysis, self-healing and tuning,with self-analysis, self-healing and tuning,will change the nature of administrationwill change the nature of administration

Day-to-Day tasks will evolve with changes Day-to-Day tasks will evolve with changes in technology and automation in technology and automation (with (with corresponding changes in job descriptions!)corresponding changes in job descriptions!)

Research and analysis will produce Research and analysis will produce smarter tools and better theoretical smarter tools and better theoretical understandingunderstanding