How many IPv4 addresses are there?
An acquaintant posted the following question on an IRC channel earlier today: How many IPv4 addresses are there? The quick and simple answer is 232 = 4,294,967,296 addresses. Is this an accurate answer? Yes, in a strict interpretation of the original question. A far more interesting puzzle is if you want to account for all the IPv4 […]
Read More → How many IPv4 addresses are there?ICANN #44
ICANN #44 is taking place in Prague these days. Sadly I was unable to attend, but the presentations are available in the open. Today’s IPv6 session would be the highlight in my very biased opinion.
Read More → ICANN #44Emails from smartd
I have wondered what emails sent from smartd would look like. Interestingly, I received such a sample from one of my systems a couple of days ago.
Read More → Emails from smartdPeriodic ZFS snapshots – 2-clause BSD license
Someone found my old ZFS snapshot script rather useful and wanted to improve it. Unfortunately I used the GPLv2 license in the original script. To accommodate my friend, I have re-released the snapshot script under the 2-clause BSD license. Feel free to use whichever license, 2-clause BSD or GPLv2, that suits your needs.
Read More → Periodic ZFS snapshots – 2-clause BSD licenseColourful and informative diagnostic by clang
clang is a breath of fresh air when it comes to deliver meaningful diagnostic of errors in program code. Not only is the diagnostic colourful on screen, clang also points out where in the source file changes ought to be made.
Read More → Colourful and informative diagnostic by clangWhen to create a ZFS filesystem?
Someone named “Edward M” posted on the freebsd-questions mailing list a question of when should we create a ZFS filesystem. I didn’t reply to any of the messages, but I decided to write this post expressing my view. In short, whenever a part of the filesystem hierarchy exhibits different characteristics, create one or more ZFS […]
Read More → When to create a ZFS filesystem?Secret splitting
A few days ago I resurrected all my files from a desktop system I haven’t used for almost six years. Below is my implementation of secret splitting as described in Bruce Schneier’s book “Applied Cryptography, 2nd edition”. The idea is basically: generate a random keystream, xor the plaintext with the random keystream, use separate couriers […]
Read More → Secret splittingendofepoch.c
Jeg børstet støvet av noen tilårskomne filer forleden dag. Jeg fant et lite program som jeg skrev en gang i 2000. Programmet teller ned til slutten av Unix-epoken. Den opprinnelige definisjonen av datatypen time_t, 32-bit heltall med fortegn, vil få overflyt i midten av januar 2038. Moderne 64-bit OS som FreeBSD/amd64 9.0 har for lengst […]
Read More → endofepoch.cZFS Delegated Administration in FreeBSD
If you trust your users well, you might feel slightly less anxious and allow your users to create new filesystems below their own home directories.
Read More → ZFS Delegated Administration in FreeBSDAre you prepared for the World IPv6 Launch on June 6, 2012?
Last year we had the World IPv6 Day on June 8, 2011. This year we’ll have the World IPv6 Launch on June 6, 2012. According to this joint press release by Akamai Technologies, Inc., AT&T, Cisco, Comcast, D-Link, Facebook, Google Inc., Internet Society, Internode, Limelight Networks, Microsoft Bing, Time Warner Cable, and Yahoo!: Major Internet […]
Read More → Are you prepared for the World IPv6 Launch on June 6, 2012?