Saturday, October 09, 2010

Installing Avast! Linux Home Edition on Ubuntu 10.10

Malware removal on Windows is a pain. Normally what I do is to run a scan using Bitdefender installed on my LiveUSB Ubuntu disk. It really helps when you can remove the most annoying viruses before booting into Windows itself for the final clean up. I've also used F-Prot before but over time I've found it to be not so effective compared to BitDefender.

Of course, it never hurts to have a second antivirus around. There's no single antivirus out there that can detect 100% of infections so it's good to have a backup ready. That's where Avast! Linux Home Edition comes in.

First, you'll need to download the .deb package from the website. It's almost as simple as installing software from Ubuntu's Software Center. On Ubuntu 10.10 you can just double click the .deb package and it'll open in Software Center. Just click the "Install" button and the rest is simple.

I used the more "traditional" method: the terminal. Here's how:

~/Downloads$ sudo dpkg -i avast4workstation_1.3.0-2_i386.deb

Either way, there should be a new shortcut available in Applications->Accessories to start up the avast! GUI. You'll be asked to enter an activation key.

Registration required
Click on the link below the key entry field and you'll be brought to the avast! site for free registration.

avast! online free registration site

A key will be sent to your email within 24 hours. Copy and paste the key and you'll be able to use avast! on your LiveUSB. The first thing you'll want to do is update the stale database before use.

avast! Engine: Invalid argument

Recent updates to avast! Linux Home gives an error when you run it.

avast! Engine caused by insufficient kernel shared memory
This is apparently due to kernel maximum shared memory settings being too conservative. Simply set the kernel max shared memory to a higher limit to workaround this.

Run the following from terminal:

~$ sudo sysctl -w kernel.shmmax=128000000

This changes the max shared memory so you can start using avast! immediately. You'll need to run that command every boot though. For a more permanent fix, use nano (or your favorite text editor) to edit /etc/sysctl.conf. Add the following to bottom of the file:

kernel.shmmax = 128000000

Reboot, and you're done. Works nicely with a LiveUSB setup.

Related posts:

Bitdefender on Ubuntu
How to remove malware from Windows
Technician's toolbox - malicious software removal tools