Defragment Mac OSX from Recovery Mode

Despite some notions that SSDs or HFS drives don’t need defragmenting, I have often read and experienced myself that defragmenting your Mac every few years will clearly make it faster.

I had some trouble running iDefrag and would like to share a little trick I learnt. Basically it will refuse to run a full defrag, while your system drive is mounted. Restarting didn’t help. Here is what I did in the end:
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Improved phising filter and DKIM signing

I noticed an increasing number of phising emails from ‘Telekom’ and ‘DHL’ making it into user mailboxes. ClamAV anti-virus together with Sane Security Phising checks does a good job in stopping zero-day phising emails.

On a different account, DKIM Email signing seems to be preferred by Google these days. So time to add that too.

Let me know if you notice any problems with that.

High-performance SSH: Install HPN-SSH on OSX with keychain integration

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I use SSH for pretty much anything from VPN, server administration, database connections or iPython work on remote machines. When working from weird places and with weird internet connections SSH become painfully slow. I already use Mosh, but that also relies on ordinary SSH to initiate the connection.

Pittsburgh University has this OpenSSH-patch to remove some bottlenecks and make it 1000% faster (they claim). Continue reading

Lazy admin’s guide to automated updates (Part 2: Python pip)

Last week we discussed Linux Debian’s apt-get update mechanism and how to fully automate essential updates. This week I’d like to demonstrate how to do the same thing for Python. I admit that keeping Python packages up-to-date is probably not half as essential as keeping internet-facing server infrastructure updated. Nonetheless I like to work with the latest versions of packages, as they might fix problems or add features. Continue reading

Shanghai PM2.5 update

I’m back in Shanghai and faced with the pollution problem once again. Here a quick update on the last months. You can clearly see a reduction in pollution around Chinese New Year, when factories are shutting down. With warmer weather the readings also seem to be lower. I don’t know the reason, but anecdotal evidence gives the same effect for Beijing. An expert from Vienna University of Economics is currently analyzing the data and correlating it with weather observations. I’ll give an update, when some results emerge.

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Introducing: (A)SPEL web stack

I’d like to officially name my current dev stack:

A.. for AngularJS. Drives the user frontend.
S.. for Supervisord. Takes care of processes.
P.. for Python. Quick way to implement almost any business logic.
E.. for Nginx. Fast web server for static files and to add SSL.
L.. for Linux.

Case study: Howard Johnson Hotel – how NOT to sell your Wifi

nessus-1Few things are more annoying than hotels, who think they need to earn some extra cash by charging people for wireless internet. Given the low to nonexistent cost of providing the service, they should also charge for warm water or fresh air, when following the same logic.

In the case of a local Howard-Johnson (HoJo) hotel, the wifi’s paywall was so badly implemented, it actually posed a threat to the rest of the hotel. Below, I will describe 4 options, anyone can use to get free internet at this particular hotel. Continue reading

Buggy Mac OSX 10.9 Mavericks update

A word of warning: Updating from Mountain lion to Mavericks is by far the most buggy process I have ever seen from Apple. At times the installer quit in the middle, My time machine volume was not recognized, network settings are lost, …

Make sure you have multiple backups and plan some downtime. On the plus-side Homebrew and my Python-packages all survived. Just make sure you use pip with a virtualenv or the –user option.

Good luck.