Today's illustrative example is about the odd things that can happenif you rename a nameserver without making sure that you tell thepeople delegating zones to you.

There are four nameservers for utoronto.ca : ns1, ns2, bay.cs, andns1.tpc.int (following local practice, I'm dropping the .utoronto.ca bit a lot). Three of those four (everything except ns1) are alsosecondaries for all campus subdomains, including the domain jpint.utoronto

A while back I wrote this , about an exceptioncreated by the cgi module when crackerssubmitted XML-RPC calls instead of form POSTs. It makes a great examplefor discussing the difference between 'secure systems' and 'resilientsystems'.

Put broadly, security is keeping people out, while resilience iskeeping operating when people attack you. The cgi module example shows that you can haveone without the other. Sometimes this may even be deliberate;an exceptionally paranoid system could shut itself down anytime it saw unexpected

We have some machines that are 'no user-operable parts inside'setups; as part of that, they have no user logins, just root . (Yes,yes, running as root all the time is bad, but on these boxes almostall we'd ever do with a plain login is su to root.)

I'm attuned to all of the regular hazards of this, but today Istumbled over a new one: how long it takes to notice that /var hadaccidentally wound up