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.
Posts tagged ‘MacOSX’
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…
I tried to upgrade my silverlight plugin from version 3 (3.0.50106.0) to version 4 (4.0.50917.0). I downloaded the DMG, followed the wizard all the way through, restarted Firefox as requested and saw that I was still at version 3… Strangely, Safari did load and use version 4, so the install was successful. So I searched my entire system fore some remains of Silverlight 3, without success.
The only place I could find the old version mentioned, was in the pluginreg.dat file in my firefox profile. I just erased this file, and it all magically worked!
I’m a fan of keyboard shortcuts. Not to memorize them, but to use them. It’s just so much quicker to hit CMD+W to close the current browser tab than it is to carefully navigate your mouse to that 12*12 pixels button. However, this didn’t work flawlessly. Sometimes I get the ubiquitous “do you want to save?” question and I have to use the mouse to click “Don’t save”; Tab doesn’t seem to work.
Until I found out how to change that setting, that is. It’s hidden in the System Preferences under Keyboard – Keyboard Shortcuts. You can change Full Keyboard Access to “All Controls”, which is the behavior I’m used to from Linux and Windows.
I sometimes pipe a command to less to study it’s output. If it’s interesting enough, I re-run the command and redirect the output to file. This approach has some limitations: the command is run twice, possibly with different output.
Obviously, I should use tee to send the output to both less and the file, but I regularly forget this. That where this hint comes in: you can save the current less-buffer to file!
In short, to save the buffer that is being displayed by a session of `less’, use its pipe-to-shell-command capability by scrolling to the top of the file and press `|’ followed by `$’ as well as entering `tee DESTINATION_FILE’ when prompted for the shell command.
Usually you don’t want to slow down your network connection deliberately. When testing networking applications, it might come in handy to simulate a worse network than you are actually on. This way you can simulate a 3G connection while actually running over WiFi.
Up until now, I used a Linux-box with netem and/or htb in the Queueing schedulers. Turns out that MacOSX can do most of this as well, using FreeBSD‘s ipfw pipes. Throtteling a single task only takes 2 commands:
$ sudo ipfw pipe 1 config bw 256kbit/s $ sudo ipfw add pipe 1 dst-ip 192.0.2.1 dst-port 80 33400 pipe 1 ip from any to any dst-ip 192.0.2.1 dst-port 80 $ sudo ipfw list 00100 pipe 1 ip from any to dst-ip 192.0.2.1 dst-port 80 65535 allow ip from any to any $ sudo ipfw pipe list 00001: 256 kbit/s 0 ms 50 sl. 1 queues (1 buckets) droptail mask: 0x00 0x00000000/0x0000 -> 0x00000000/0x0000 BKT Prot ___Source IP/port____ ____Dest. IP/port____ Tot_pkt/bytes Pkt/Byte Drp $ # do whatever you want $ sudo ipfw del 00100 $ sudo ipfw pipe del 00001
Google is my favorite search engine; I use Maps regularly and enjoy Earth as well. I am however concerned about privacy using all these cloud-services. Privacy has a lot of different meanings. Here I’m talking about the control meaning: I want to be in control over my stuff, being it my computer, my mails or my documents.
My concert just got another boost when Growl notified me that a new volume was mounted. I was surprised, since I was laying back, watching a movie… The volume mounted was “GoogleSoftwareUpdate-1.0.6.1054″.
I do have Google Earth installed on my machine, but don’t remember asking it to update itself, definitely not when it’s not even running!
After some digging around, I found the dmg hiding in ~/Library/Caches/com.google.UpdateEngine.Framework.501/Downloads/com.google.Keystone.dmg. Apparently, I’m not the only one who noticed this. This updating seemed to be launched from launchd and can be disabled by removing or disabling the plist-file:
Disabling the startup item can be done by deleting the file ~/Library/LaunchAgents/com.google.keystone.agent.plist or adding a new “Disabled” property to it (in case you want to keep the file):
<key>Disabled</key> <true/>
I got another toy to play with: A digital multimeter with RS232 interface and True RMS power measurement. Sadly, it comes with Windows-only software, which I interpreted as a challenge!
Continue reading ‘VoltCraft VC-940 protocol reverse engineered’ »
When I’m debugging serial communications, it’s very useful to run the standard application inside a VM. This allows me to connect the virtual RS232 port to the physical one with socat, which provides me with a detailed log of every byte.
The VMware products under Windows and linux have the option to connect their serial port to a “named pipe“, although it’s more a socket, since they allow bidirectional communication. Strangely enough, VMware Fusion, the Mac product, does not have this option.
Continue reading ‘Connecting a serial port from VMware Fusion to a unix socket’ »
