Install nfdump and nfsen netflow tools in Linux

Using nfsen it is possible to view IP traffic statistics on Linux interfaces including the graphs showing data sent and received (see the screenshot to the right) as well as historical information about all data transfers. So after you’ve configured nfsen and nfdump to monitor traffic on certain Linux server or router you’ll be able to answer the following example questions: What IP was downloading data through 48161 last Wednesday? […]

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Sendmail for virtual users with procmail, spamassassin and dovecot

Today I’d like to describe setup of sendmail that allows to establish receiving of e-mails for certain domain and sort incoming messages between virtual users. Those users must be able to fetch received e-mails via POP3 or IMAP protocols with or without TLS encryption. The key aspect of this kind of setup is that we will make sendmail working with virtual users which aren’t present in /etc/passwd so once it’s […]

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How to monitor traffic at Cisco router using Linux (Netflow)

By default Cisco IOS doesn’t provide any traffic monitoring tools like iftop or iptraff available in Linux. While there are lots of proprietary solutions for this purpose including Cisco Netflow Collection, you are free to choose nfdump and nfsen open source software to monitor traffic of one or many Cisco routers and get detailed monitoring data through your Linux command line or as graphs at absolutely no cost. Below is […]

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Create Encrypted Filesystem Within a File (truecrypt way)

Some time ago I’ve written an article named 16 GB encrypted candy file describing how to create encrypted filesystem within regular file. After quick research it became clear that cryptoloop is vulnerable and there is open exploit available on the web: see it here (thanks to everybody who commented that article). So I don’t recommend to use cryptoloop but instead take a look at truecrypt that makes it possible not only […]

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Install Windows after Ubuntu Lucid Lynx

Sh*t happens. There is no more applications to manage my 6th generation iPod Classic 160 GB under Linux/Ubuntu. I have to install Windows as the second operating system along with newly installed Ubuntu Lucid Lynx (it rocks but this is for another post) to run iTunes. For rather long time I’ve been using gtkpod, amarok, banshee, exaile or rhythmbox to sync my ipod under Linux/Ubuntu and load my music collection there. […]

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