Restarting cloudfoundry apps without downtime

When running an application on Cloudfoundry it’s possible to start multiple instances of an application. This might be for performance reasons, but also by means of reliability. When restarting an application the default behaviour is first stopping all instances of an application and the starting them again. This results in a small downtime when there is no running instance available. Let’s see how to improve this approach. Continue reading

Determining content type with Apache Tika

About Apache Tika

The project is hosted by the Apache Software Foundation. It supports detecting various file and content types. There is a full list of supported formats. When having a look at the list that displays the supported formats, many document formats are listed in there. E.g. text/plain, text/xml, the propritary Microsoft OOXML or the office standard Open Document. Furthermore images (image/gif, image/jpeg, image/bmp or image/tiff), videos (video/avi, video/mpgeg or video/mp4) and audios (audi/ogg, audio/x-wav or audio/mpeg) can be recognized by Tika. Even feeds (application/rss+xml, application/atom+xml) may be recognized. And many, many more … Continue reading

How to debug encrypted HTTP traffic

When developing software, sometime it’s necessary to sniff the traffic that is transmitted between two computer systems. For that purpose tools like wireshark or tcpdump may be useful. Wireshark is a great tool, but when handling encrypted connections it is not possible to decrypt the traffic without having the key used for encryption. When sniffing http traffic the private key of the certificate is required to decrypt the information. But when talking to a foreign server, without having its private key another approach is necessary. Continue reading

Compressed Memory

When using swap the system is going to be dramatic slow and maybe hangs for seconds as the performance of the next level memory is dramatically slower then random access memory. In case there is not enough physical RAM and swapping happens really often, there is a way to compensate this approach a little bit by using compressed in-memory swap space. Continue reading

Installing Chrome / Streaming Netflix on Ubuntu

Currently using legal video streaming is a quite tough topic. As drm mechanism prevent most of the users to use legal video streaming on Linux. I don’t want to make some advertisement, but using Amazon Prime/Instant Video, Google Play, Netflix etc.. is not working out of the box. But Netflix provided a way to use Google Chrome for streaming. Continue reading

Deactivate Firefox search in location bar

Using the Firefox search within a local network, Firefox uses the integrated search instead of trying to access the server in case it is not a full domain name. This is really annoying, especially when you try to access servername. Firefox tries to search for servername instead of trying whether there is a server with exactly that namke. But there is a solution for that. Continue reading