Author Archives: David Chappell

Updating Webmin’s self-signed certificate

When SSL is enable in Webmin it creates a self-signed certificate which is stored in the file /etc/webmin/miniserv.pem. I recently upgraded a server from Debian 7 to Debian 9 and discovered that Webmin would no longer start: Starting Webmin server … Continue reading

system administration

Darwin and Pasteur

On November 24th, 1859, the naturalist Charles Darwin published a book entitled On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life. In it he offered his views on … Continue reading

science

Newton’s views on science and theology

For the second edition of his Principia in 1713 Newton wrote an essay known as the General Scolium (introduction) in which he defends his views on several scientific and theological questions. There is an English translation of the expanded version … Continue reading

science

Institutional Memory

Knowledge is a slippery thing. If we don’t take care we can lose it. Organizations loose it when members leave or retire without passing it on to their replacements. Suddenly the organization does not know how to do part of … Continue reading

liturature, society

Fire Dogs

This following story is from Lev Tolstoy’s First Russian Reader of 1875. This is my translation. As far as I know it has never before appeared in English. (You can read the original at ReadyRussian.org.) Fire Dogs A True Story … Continue reading

liturature, russian

Electrical Power and Power Loss

Basic Electrical Units A volt is a unit of electrical potential. Electrical potential in turn is the force which a power source (such as a battery) applies to a connected device in order to push electrons through it. Electrical potential … Continue reading

electricity

Communicating Clearly About Computing

Those of use who work in IT are frequently called upon to explain our work to people who are less familiar with computers than we are. It should be our goal to speak and write as clearly as possible. To … Continue reading

english, writing style

Waiting to Bite: BIND and Invalid Zone Files

It looks like Webmin lets you create DNS entries which BIND 9 does not like. When it sees one it refuses to load the whole zone and keeps what it has in RAM. This may go unnoticed for months until … Continue reading

dns, system administration

Draco’s Policies were Draconian

Have you every wondered why we call a harsh policy “draconian”? This is one of those words which comes from the name of a famous person.

language

Flowroute

I have been grieving ever since Voicepulse canceled its flexrate program and been looking for a new low-price provider with good quality.

asterisk, voip