Mailserver....................

Problems are solved, software praised and a few typos busted as the LXF team answers your emails.

I recently picked up a copy of LXF188 and find it a treasure of useful information. I’m a newbie to Linux under the hood, though I have been using Ubuntu exclusively for home use since at least 2008. But while I love everything about Linux, I have had the misfortune to have been hacked, having surfed the net primarily over public unsecure Wi-Fi connections.

Using my laptop in the local public library I have been experiencing a few problems. My [connection] speed spontaneously changes from 56Mbps to 1Mbps. Headphones suddenly stop working. The browser screen greys out or closes after visiting certain news sites. Then there’s the inability to run the su command. The inability to log into my laptop except at certain times. People and groups other than myself being given access to my laptop.

I would appreciate any information you can give me on securing my machine from intrusion. How can I find and erase a rootkit? What are the attack vectors for Ubuntu and Linux, and how can I protect against them? What services should be enabled/disabled?

I would also like to know where can I find the correct configuration files for my Linux distros. What should a ‘normal’ config file look like, and what would distinguish it from a file that has been tampered with? PW Neil says: Wireless connection speeds can vary wildly on the fly, but I’m not entirely sure what the cause of some of your other issues is. However, regularly using unsecured Wi-Fi connections is clearly a bad idea. A detailed guide to system security is beyond the scope of the Mailserver section, but we’d strongly suggest using a Live CD or USB-booting version of Tails ( https://tails.boum.org), just to see if your many issues disappear. At least then you can ascertain if your system is indeed being hacked or not.

Speed daemon

The SpeedUpLinux article [ p32, LXF188] was very interesting, and I look forward to playing with some of the suggestions. It made me think