simplr's questions

Back in the days of Redhat 9 I set up networks using dumb terminals that used telnet to log in to the server. And simply by deleting the 'X' in /etc/passwd for the user, the user could log in with a user name only. This allowed easy operation of the workstations.

Security is not a concern. The Linux server is located at the same premises and is not locked away - so anyone with malicious intent could have full access to the system. However, the users who log in with just their user name get sent, by means of a login script, into the application program and get logged out automatically when they quit the application. The Internet access is only with password protected SSH on a non-standard high port.

In recent years I have been using Ubuntu for the servers and I have not been able to eliminate the requirement for a password. The best I could do was allow a null password, but the user still had to press Enter to submit the null password after entering the user name.

I am now planning to replace the Redhat 9 servers next year to Ubuntu Lucid Lynx and would like to keep the old dumb terminals in operation as before.

Can someone please tell me how the adjust the configuration files in /etc/pam.d so as to emulate the old RH9 telnet behavior while still keeping the Internet access secure?

I have servers which are still running well but are over 5 years old. They are still doing the job perfectly and there will be no advantage to upgrade the servers, should I just let them run forever or should I schedule maintenance to replace the servers, or parts thereof, with new hardware? I fear that a server failure might cost data loss and more down time than scheduled maintenance. These servers are used for on-line point-of-sale, accounting, CRM and management information.

Preventive maintenance, such as replacing fans and vacuuming out dust, is not possible due to the remote location of the servers.

Also keep in mind the "bathtub curve" of failure rate with time. New hardware is more likely to fail than hardware that has been burned in for a while.

How do you tell a client who is very happy with a long-time trouble-free server that he now has to spend money to replace it because it is too old?

Finally, are there any monitoring tools for hardware problems such as voltage, temperature and fan speed that can be run remotely?