I wanted to write a few sentences on the xferlog, since I know that not many people pay attention to it, but it really can be useful.

For example, you have an ftp user who does some actions, deletes files, writes file, reads, etc. All these actions are stored with timestamp in xferlog.

System administrator can find out specifically what happened with the files, that are stored or delete, who deleted them, and when.

It is usually located in /var/log/xferlog

It stores a format that will give you as follows, current-time, transfer-time, remote-host, full-size, file-name, transfer-type (binary/ascii), special-action-flag (compressed/uncompressed), direction (outgoing/incoming), access-mode, username, service-name, authentication method and completion-status (complete/incomplete).

So basically, all the information is there for the system admin who wants to analyze the ftp actions.

My current use was to find successfully uploaded files. One command:

awk '($12 ~ /^i$/ && $NF ~ /^c$/){print $9}' xferlog

and I got them all.

So I wanted to share this with you as you might find it useful in some situation. Drop a comment if you want to ask me something, or if you have a problem with an investigation of a specific case.

I want today to present yum vs apt-get differences. I'm sure a lot of users use Fedora Core, and are thinking about switching to Ubuntu or Debian.

The major difference between these systems is your ultimate application for installing, updating and managing packages for the distribution.

For those users who are switching from Fedora to Ubuntu, the yum tool is replaced with another great tool apt-get.

Installing is basically the same, you do 'yum install package' or 'apt-get install package' you get the same result.

Yum automatically refreshes the list of packages, whilst with apt-get you must execute a command 'apt-get update' to get the fresh packages.

Another difference is upgrading all the packages. With yum you did 'yum upgrade' and with apt-get you get a new option 'apt-get dist-upgrade' which will hopefully upgrade your whole distribution.

There are a few more tips for apt-get which I will name briefly here:

dpkg --list (to get the list of packages), apt-cache search [package_name], apt-get clean (to get packages removed from the local cache directory), etc.

Finally, I wanted to mention that apt-get mostly works with .deb packages, though the tool can be installed on Fedora distribution to serve .rpm as well.

Its configuration is served from /etc/apt/ and there you will find sources.list with respective repositories for packages needed for user's proffered distribution.

I probably forgot to mention some other important differences, so feel free to correct me and drop a comment.

If you already use this tool, drop a command to join the hood. If you don't, feel free to ask any questions or add something to my introduction.

Although I do manage APF tool on my work, just recently I have put it in my personal use.
APF is netfilter (iptables based) firewall system designed to cover all advanced needs of your workstation for net filtering.I will just mention a few of its features that are most interesting to me and maybe will draw your attention:
- Detailed and well commented configuration file (very easy to modify and adjust to user's personal needs)

- Reactive address blocking (RAB), next generation in-line intrusion prevention

- Fast load feature that allows for 1000+ rules to load in under 1 second

- Spamhaus don't route or Peer List support to ban known ìhijacked zombie IP blocks

- Intelligent route verification to prevent embarrassing configuration errors

Those are just a few, they have on their website a lot more, that or more or less useful. Overall, I think it's a good practice to introduce APF to your workstation, and let the filtering go at ease.Anyhow, if you feel curious about it, google "APF firewall" and it'll bring you right to their website.
For you who have experience with APF or maybe even better project, please feel welcome to comment.