Reduce Swappiness

Most laptops have enough RAM installed that the swap space on the hard disk shouldn’t really be used. Yet the default setting for swappiness in Ubuntu is 60. By lowering it to 10 we can reduce the number of read/writes the the hard disk. This is especially handy for netbooks with solid state drives in them. To reduce the swappiness, follow these steps:

1. sudo sysctl -w vm.swappiness=10
2. Add the following line to /etc/sysctl.conf
   vm.swappiness=10

Preload

Preload is an adaptive read-ahead daemon that monitors running applications and analyzes them for commonalities. It then uses this data to predict what applications you might run and preloads them into memory. The result is faster startup times for commonly used programs. Installing preload is as easy. Just run the following line in a terminal window:

sudo apt-get install preload

» For further explanation, read this article on loading applications quicker in Ubuntu using preload.

Boot-Up Manager

The Boot-Up Manager (BUM) is a useful utility for starting and stopping boot-up scripts. Once installed it will appear in the System -> Administration menu. You can use BUM disable unnecessary boot-up scripts that may be slowing down your boot time. For example, I disabled saned, an API library for scanners, because I know I’ll never be attaching a flatbed scanner to my laptop. To install BUM:

sudo apt-get install bum

» Read the documentation for Boot-Up Manager

Startup Applications

If you are using Gnome for your desktop manager there will be an option to select which applications are started when you login. Go to System -> Preferences -> Startup Applications and uncheck the programs you don’t need. For example, I disabled the Evolution Alarm Notifier because I don’t use Evolution for setting alarms. I also disabled the Remote Desktop server, UME Desktop Launcher, and UNR Launcher. Just be careful to uncheck them and not remove them. In the case that you’ve removed something critical, you’ll want to be able to get it back.

Replace Metacity with Openbox

Openbox is a minimalistic and lightweight window manager that is known to run much faster than metacity, its bulkier counterpart. And you can easily get it working while still using Gnome as your window manager / desktop environment. By running Openbox inside the Gnome environment your desktop will become cleaner and faster. To install it, follow these steps:

1. Install openbox using:
   sudo apt-get install openbox obconf openbox-themes
2. Setup openbox as the default window manager by adding an entry in Startup Applications.
   To do this, go to System -> Preferences -> Startup Applications and enter the following:
   • Name: Openbox
   • Command: openbox ––replace

   Note: According to the Openbox documentation you can make it the default by choosing the GNOME/Openbox session when logging in and saving this as your default session. However, this functionality is broken in 9.04. The above steps are a workaround until this is fixed.

3. Choosing the Openbox theme and other configuration settings
   Go to System -> Preferences -> Openbox Configuration Manager to choose a theme you like and to update other settings such as Appearance and Windows.
   Note: changing the Desktops setting doesn’t effect the Gnome applet controlling the number of desktops. To change the number of desktops, you will need to revert back to Metacity and change them, then re-enable Openbox

» More information, documentation and screenshots available at the Openbox web site

That’s all for now

I found that making these few simple changes decreased load times on my older laptop significantly and made my newer netbook more minimal. Hopefully, these tips will help you as well.

• Background
• Configuring the Sonicwall Router
• Installing Openswan
• Configuring Openswan
• Starting and stopping the VPN connection
• References

Background

Pelago is a web design and development agency in Santa Barbara, California. Since our humble beginnings in August of 2000, we’ve seen the Internet landscape evolve exponentially in the last nine years. Our most current challenge as a creative and engineering agency is in embracing diversity in platforms and the inevitable shift towards the remote office. We use three different operating systems — Windows, OS X and Linux — on a daily basis. In addition to developing web-based project management software that is compatible with all three platforms, our designers and developers rely on them inside and outside of the office. Tunneling through the firewall from outside the office was our next requirement for embracing a diverse and distributed remote office.

Our SonicWall router makes it easy enough to establish a VPN connection using Windows. There is a client that can be downloaded from the SonicWall web site. What about other operating systems? Our developers often use Ubuntu Linux from home and required a way to VPN into the office. Once established, a VPN connection allows access to development servers, remote desktops, and other network resources inside the firewall; so you can see why it would be essential for the remote office.

The problem, as most Linux users out there already know, is that setting up a VPN connection in Ubuntu Linux is not very easy. After much trial and error, here is how we got the VPN working on Ubuntu Linux using Openswan.

Configuring the SonicWall Router

Login to your SonicWall router admin and make the following adjustments to the VPN settings.

1. Click on the VPN link and note the Unique Firewall Identifier for your SonicWall router. You will need it later for the value sonicwall.unique.identifier.
   
2. Under VPN Policies, create or edit the ‘GroupVPN’ policy.
3. Click on the General tab and set the following:
   
   • IPSec Keying Mode: IKE using Preshared Secret
   • Shared Secret: shared.secret.key (enter your secret key here)
4. Click on the Proposals tab and set the following:
   
   • IKE (Phase 1) Proposal
     DH Group: Group 5
     Encryption: 3DES
     Authentication: SHA1
   • Ipsec (Phase 2) Proposal
     Protocol: ESP
     Encryption: 3DES
     Authentication: SHA1
   • Enable Perfect Forward Secrecy (checked)
     DH Group: Group 5

Installing Openswan

If you are using Ubuntu, open a terminal window and type in:
sudo apt-get install openswan
The install will ask you a few questions about how you want to set it up. Select the suggested default for each step. This will install Openswan and create the ipsec.conf and ipsec.secrets configuration files.

Configuring Openswan

Add the following connection parameters to your /etc/ipsec.conf file:
conn sonicwall
     type=tunnel
     left=192.168.2.31 #your IP
     leftid=@GroupVPN
     leftxauthclient=yes
     right=xxx.xxx.xxx.xxx #IP address of your sonicwall router
     rightsubnet=192.168.1.0/24 #gateway IP for your LAN. This will work for most
     rightxauthserver=yes
     rightid=@sonicwall.unique.identifier
     keyingtries=0
     pfs=yes
     aggrmode=yes
     auto=add
     auth=esp
     esp=3DES-SHA1
     ike=3DES-SHA1
     authby=secret
     #xauth=yes


Update: After upgrading to Ubuntu 9.10 a few things changed in the conf file. First, I had to comment out ‘xauth=yes’ as it was throwing an error.

Add the following line to your /etc/ipsec.secrets file
@GroupVPN @sonicwall.unique.identifer : PSK "shared.secret.key"

Starting and stopping the VPN connection

Starting ipsec and opening the VPN connection
sudo ipsec setup ––start
sudo ipsec auto ––add sonicwall (note: if you change the configuration files, you'll need to run 'sudo ipsec auto ––replace sonicwall' to reload the file)
sudo ipsec whack ––name sonicwall ––initiate

Closing the VPN connection and stopping ipsec
sudo ipsec whack ––name sonicwall ––terminate
sudo ipsec setup ––stop


References

The following links were useful for getting the VPN connection up and running on Ubuntu Linux:
Openswan wiki page for SonicWall routers:
http://wiki.openswan.org/index.php/Openswan/SonicWall
SonicWall PDF instructions for using Agressive Mode and IKE with Pre-shared Keys
http://www.sonicwall.com/downloads/SonicOS_Enhanced_to_Openswan_Using_Aggressive_Mode_IKE_with_PreShared_key.pdf

11/05/2010 Update:
We are now on our third SonicWall Router. The original 170 didn’t have enough features for us. It’s replacement, the 2040 recently went belly up. We are now running on the 2400. When we made the upgrade the Linux VPN stopped working. Checking the logs on the 2400 revealed a message stating the IDs did not match during Phase 1 IKE. It took some googling to figure out but the fix was to change the leftid so that it matched the name of the security policy. In this case, GroupVPN:

     leftid=@GroupVPN


Another update you can make to the above configuration is to add the following lines to your configuration to allow VPN access from any IP:

Add interfaces

config setup
     interfaces=%defaultroute

conn sonicwall
     left=%defaultroute


• NTFS writing
• Encrypted hard disk
• Easier dual screen configuration
• Gnome 2.20 Desktop

Why is Ubuntu our favorite? Because it is easy to install and most closely mirrors the desktop environment. We’ve installed a lot of distros here at Pelago. Our developers like SUSE, our sysadmins like RedHat and CentOS, and the rest of us love Ubuntu.