This is an answer to some of claims he stated.
Ronald starts with some valid points about default directory permissions. Right, we choosed 0755. There are valid use cases for 0700 and 0755. It’s impossible to set up a fit-for-all solution.
Next claim is that Ubuntu supports IMAP2 and POP2. Too bad Ronald can’t read netstat’s output correctly. Ubuntu (it’s actually dovecot we talking about here) doesn’t support POP2 and IMAP2. What Ubuntu/deovecot supports are IMAP4rev1 and POP3.
Before making this claims, author should know that IMAP4 is an extension of IMAP2, so it uses the same port as imap2. As you can’t define multiple names to one port in /etc/services, sane practice is to put imap2 there. netstat reads /etc/services and then claims that protocol is imap2.
Following this is claim that Ubuntu opens bootpc and bootps UDP ports when there’s a static network configuration. bootpc is clear sign that you have a running dhclient, Ronald. If you configured your network to a static IP during installation, you won’t have dhclient running. bootps, on the other hand, is a clear sign someone is running dhcp server.
So, while there are some valid points in that article, author should know better before writing articles like this one.