As mentioned before, when switching to IPv6 (or more realistically, to dual stack) one of the things that might not work out of the box is VPNs. I decided to put some effort in it to get it to work anyway.
Together with most of the internet, we tested IPv6 on World IPv6 day last week. I won’t go into details on what IPv6 is and why it’s important. Although IPv6 has been tested intensely in isolated networks, this is the first time it was tested on such a large scale. Technically, the participants would just add AAAA-records for their websites to DNS. This small change causes a huge effect. Since most browsers are configured to prefer IPv6 AAAA-records over IPv4 A-records, this causes all IPv6-connected users to suddenly connect over IPv6 instead of IPv4.
For the most part, this major changeover happened without as much of a hitch. In fact, if I hadn’t known it was World IPv6 day, I wouldn’t have noticed anything. But I’m not a normal web-user, so I did notice some issues.
Continue reading ‘World IPv6 day – lessons learned’ »
I was under the illusion that a Time Machine backup would do as they claim:
You can set up Time Machine to automatically back up all your important files, including your documents, music, photos, applications, and any other items you keep on your hard disk.
I consider my iTunes authorizations important, but apparently Apple does not. Seems that these are specifically excluded from backups… Removing the “SC Info” line from the /System/Library/CoreServices/backupd.bundle/Contents/Resources/StdExclusions.plist file solved this.
I know I should have de-authorized my machine before reinstalling, and I know you can “de-authorize all” to fix this as well; but it’s pretty disturbing to see iTunes remove all your applications from your iPhone…
The new installs of Belgacom’s DSL internet connection are actually fairly descend. They provide a “b-box 2” which provides 2 wired 10/100base-T ports and an 802.11g access point. It consumes 10.1W of power once booted (21VA with a cosφ of .47, measured with 241Vac), which costs around €22/year at the current prices. The box has a built-in router which performs the PPPoE connection and does the NAT. While this setup is perfectly fine for a regular setup, obviously I wanted something more…
Continue reading ‘Getting a public IPv4 address with Belgacom’s BBox-2’ »
I regularly watch log files in real time using the highly appreciated tail -f command. But I usually find myself manually inserting newlines to give a visual clue of which log-lines happened together. Obviously the timestamps in the lines tell you the full story, but it’s not that visually appealing.
I assume I don’t have to introduce the concept of spam. Fighting spam can be done on different levels. A first line of defense is the mail server receiving them. There are several checks it can perform. Here is my configuration of Postfix.
To get secure access to internal networks, one usually employs one of the many variants of a VPN. When connecting from a normal computer, you can install basically whatever variant you wish. When using devices such as smartphones however, the number of supported VPN technologies is usually limited. Especially on non-open platforms such as the iDevices by Apple, you can not add VPN software yourself, contrary to the Android platform.
In this post, I’ll explain how to set up an IPsec (without L2TP) tunnel endpoint on an Ubuntu server, capable of handling an iPhone/iPad/iPod/iWhatever. The users will be authenticated against an LDAP directory.
Continue reading ‘iPhone compatible IPsec VPN on an Ubuntu server, with LDAP authentication’ »
When programming with multiple files/modules, dependency tracking is always a big issue. GNU Make calculates the correct order to compile in, but is only that smart. It does know that if a .cpp file changes, the corresponding .o file needs to be updated. But a change in an included header can go unnoticed.
While debugging a strange problem today, it was exactly that last scenario: A change in a header file did not cause a recompile, which left me debugging an old version of the binary. So I wanted to include the dependencies of .cpp files on the included headers in my Makefile. But since I’m too lazy to do it myself, I wrote a script.
dd-wrt has built-in support for a whole list of Dynamic DNS services. Unfortunately, they only support HTTP-based services. I use a standard RFC2136 DNS update. Here’s how to add nsupdate support to dd-wrt.
Continue reading ‘Using nsupdate in dd-wrt’ »
Although the big builds of dd-wrt contain IPv6 support, it doesn’t support ip6tables. Hence, I choose to use the mini build (which gives me the most free space) and add the missing parts myself. I shamelessly used OpenWRT modules to save me the trouble of figuring out how to compile each library. (Unfortunately, my router isn’t supported by OpenWRT, so I need to stay with dd-wrt for the base system).
