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Any operating system that contains the letters B, S and D usually conjures images of geeky elitism, arcane interfaces and the undead world of UNIX. Despite its similarity, this is an image Linux has largely been able to shake off, thanks to its friendly graphical installers and configuration tools. But BSDs can offer a unique insight into what has made Linux popular, as well as an opportunity to hone your command-line and trouble shooting skills in a world that might be getting too easy. And while you do need a little technical confidence to get any BSD system up and running, it’s not half as difficult as it first appears.

FreeBSD is not as demonic as its logo might suggest. Honest.

FreeBSD is a the most popular implementation of version 4.4 of the Berkeley Software Distribution. This was the original BSD, a version of UNIX that was developed between the late-70s and the mid-90s and used a famously liberal licence. This licence has meant that anyone can use, copy and redistribute and re-implement its code and APIs. Which is exactly what FreeBSD attempts to do, alongside other projects like OpenBSD and NetBSD. In turn, there are many projects like Apple’s OS X that build upon the foundations in FreeBSD, all thanks to the liberal licences of the original.

Step 1: Prologue

There are several important differences between FreeBSD and Linux, but the most fundamental is the kernel. The term ‘Linux’ is most often used to refer to the entire operating system, from the boot code and drivers to the desktop and the applications. We’d call Ubuntu, Fedora and OpenSUSE different versions of Linux, for instance. But this definition isn’t accurate. ‘Linux’ should only really refer to the kernel – the chunk of code at the heart of the system that deals with hardware, networking, drivers, storage, CPU and process management, and the BSD kernel is entirely different.

The Linux kernel that was originally developed by Linus Torvalds, and it’s still the only part of the whole operating system he has control over. The remainder of what makes a complete operating system, the windowing environment, the desktops and the applications, are pulled from open source project that are mostly using one of the the GNU Public Licences. Hence, the official name for the entire Linux operating system is really GNU/Linux to show that there are two parts of the whole project. Which is why replacing the kernel isn’t a trivial operation.

Don’t be scared of text mode. It’s part of Linux’s legacy, and serves a very useful purpose.

Any new kernel needs to be broadly compatible with Linux so that the remainder of the software stack can be ported without too much difficulty. Fortunately, both FreeBSD and Linux are UNIX-alike, which means there are many similarities, and the result is that with a standard installation, you’ll find many of the tools you’re already familiar with, albeit in a different configuration.

Many system administrators feel FreeBSD is has been a more stable choice for servers over the years, and that it can out-perform its cousin on certain tasks. It’s also a great choice if you want to run a server on limited hardware, as the requirements for a BSD-based system are often less than for the Linux equivalent. FreeBSD, for example, lists its minimum requirements as a 486 CPU with 24MB RAM, which is quite staggering in today’s world of terabytes and quad core processors. FreeBSD is also a i386-based platform. There are ports to other processors, but the project’s focus has always been compatibility with Intel’s standard architecture, and as a result, could be better suited to the majority of machines that parts of the Linux kernel.

Step 2: Installation

While there are Live CD versions of FreeBSD, the traditional install disc is still the most common medium for getting hold of the latest version. But you’ll need to steel yourself against its antiquated installation mechanism.

When you boot your machine with the disc in the drive, the first thing you’ll see is the black and white ASCII art of the install menu. You won’t see any other graphical embellishment until you’re able to boot successfully into a working desktop. For most installs, you’ll need to choose option 1 from the menu, but if you’re using an older machine, you may want to try 2 (with ACPI disabled) to avoid any potential problems.

Unlike trial Linux installation packages like Wubi, installing BSD has a tendency to be destructive. Make sure you’re not going to obliterate anything important before continuing.

You’ll then have to wait a few moments while various kernel messages scroll by before you’ll see the text-based installation and configuration screen. If you’ve used Debian, this kind of text installer will feel familiar. There’s no linearity to the install process. You can move backwards and forwards through the various options, and continue to make adjustments to the installation until you quit the installer and restart the system.

For a basic, working environment, you will need to do at least the following. Select the second option in the menu to initiate a ‘Standard Install’ and read the information on the screen that follows. The next page displays ‘fdisk’, the disk partitioning and formatting tool. Press F1 for documentation, but if you’re using your entire hard drive for this installation, press ‘a’ to select everything, followed by ‘q’ to apply the changes. This will delete everything currently on the drive, so be careful.

The next page will ask if you want to install a boot loader, which is the menu that lets you choose between whatever operating systems you have installed. Choose the second option (BootMGR), and on the following page, you need to create the various partitions used by FreeBSD using the same fdisk-like interface we’ve just seen.

Once again, if you’re using an entire drive for the installation, you can just press ‘a’ to let the installer create the most appropriate array of partitions followed by ‘q’ to make the changes permanent.

The next page will ask you to choose a distribution. Unlike a Linux distribution, FreeBSD uses the term to refer to the default selection of packages that are to be installed. Select ‘Custom’ and add ‘base’ and ‘kernels > GENERIC’ to your installation.

This will give you enough package to get a working system, and we’ll need to add the desktop environment at a later stage. Return to the ‘Exit’ option at the top of the list and press space to jump into the package installation routine.

Step 3: Post-Install

After all the preliminary configuration has completed, you’ll be asked whether you want to configure any Ethernet or SLIP/PPP devices. Select ‘Yes’ if you are connecting to the internet through your machine’s ethernet port, and you should see your adaptor listed in the top of thew connections list. Choose the adaptor, say no to IPV6, say yes to DHCP and skip through the configuration page to the OK button. Say ‘no’ to your machine being a network gateway,’no’ to enabling any inetd services or running SSH, FTP and NFS server and clients, and don’t edit the console settings. You can safely setup a timezone for your machine and enable the PS2 mouse emulation if you’re using one.

Don’t worry too much about your initial selection of packages. You can easily add more later.

Say ‘Yes’ to the next question, and you’ll now be looking at the package manager. This is where you choose what applications you want to be installed on top of the default option we chose earlier, and there are thousands of packages to choose between. For a simple setup, jump into the ‘x11’ menu and select the ‘kde4-4.3.1′ package. It’s exact name will depend on the version of FreeBSD you’re playing with. If you’re not a fan of Gnome, you could also choose ‘gnome2-2’ from the same list of packages. Selecting either will also mark their dependencies for installation. You also need to select xorg-7, and any other packages you know you’re going to need.

When you’re ready to go, jump back to the top package list, select ‘Install’ and press space. You’ll need to wait a while for all the packages to install. The next step is to create a user account. You can do this by saying ‘Yes’ to the option, then selecting ‘Add User’, and entering a user name in the page that follows. Select OK to make the change permanent and exit from the users and groups menu. You’ll then be asked for the system manager’s password, and you’ll need to type this twice.

After that, you can say ‘No’ to the post-install configuration request and wait for your machine to reboot. You’re now at the point where you should have a basic, working installation, and you can quit from the installation menu and restart your system.

Step 4: Configuration

When your machine re-appears, you’ll be greeted by the sombre monochrome of the command line. Login as ‘root’ with your system manager’s password. For both Gnome and KDE, you need to add the following two lines to the ‘/etc/rc.conf’ configuration file:

dbus_enable="YES"
hald_enable="YES"

Unfortunately, you’re going to need to use the ‘vi’ text editor. Type ‘vi /etc/rc.conf’ to load the file. Press ‘i’ to enter insert mode, move to a new line and type the following. Press escape to exit insert mode, followed by ‘:wq’ (without quotes) to save the changes and quit the editor. Next type ‘reboot’ to restart your system.

FreeBSD doesn’t come with a desktop activated by default, but it’s simple enough to change.

When you get back to the login screen, enter your user account details this time, and when you get dropped back to the command line, type ‘vi .xinitrc’ and add the following line to the file:

exec /usr/local/kde4/bin/startkde4

This is telling your system that when the X.org graphical system starts, you want KDE to be used as your desktop environment. Save and exit vi.

Step 5: Launch Desktop

Usually, at this point, you need to create an ‘xorg.conf’ file to define the display properties for your machine. But recent releases of the X server are able to create a working configuration without any further editing. Which means typing ‘startx’ is all you need to do to launch a graphical environment running KDE. If this doesn’t work, then you will need to create create a working /etc/X11/xorg.conf file.

But with FreeBSD 8, it’s more likely that you are now looking at KDE running through its Akanadi porting routines as it builds up a configuration for your desktop. After a couple of minutes, this will leave you with a KDE desktop running on-top of FreeBSD, and you’ve just earned another trophy for your awards cabinet.

At long last: a GUI! And one of the more stable interfaces you’ll find. Here’s hoping BSD serves you well.

This is exactly the same KDE you’ll find on Linux, and you’ll be hard pressed to find any difference between the way it works on FreeBSD and the way it works with Kubuntu. It’s only when it comes to system configuration that you’ll notice because FreeBSD doesn’t have any graphical configuration tools, which means if you need to change anything, you’ve got to be prepared to go back to the command line. But that’s another story.

See also: PC-BSD 8.0

If you’ve followed the main text to install a shiny new version of FreeBSD, you might have noticed that the install mechanism really wasn’t all that shiny or new. It reality, it feels ancient. But this doesn’t mean that the operating system has been languishing unloved and undeveloped, it just means that making the installer easier to use is low on the priority list.

Fortunately, this being open source, demand for a better way of doing things has led to several alternatives, the best of which is PC-BSD, which you’ll find at www.pcbsd.org. It does several impressive things. Firstly, it replaces the tepid monochrome installer of FreeBSD with a graphical application much-more in-line with its Linux counterparts. It will also automatically install and configure a recent version of the KDE desktop, which should mean you can get productive with a FreeBSD system as quickly as possible, without touching the command line, and there’s a wonderful wiki full of helpful documentation.

This means you can install PC-BSD by placing the disc in the drive, rebooting your machine, answer the questions that appear and wait for the operating system to install. You won’t even need to worry about manually partitioning your drive unless you want to create a custom configuration.

Another important difference is that it PC-BSD doesn’t use the same package management as FreeBSD, although you can still get to it if you need to. Instead, package are available as single files with the ‘.pbi’ file extension, which can then me installed with a simple click. It’s more like how packages are handled on OS X, and is far better than the weird world of dependencies you find on Linux.

Winners of the first eLearning Africa photo competition will be featured in an exhibition at the fifth pan-African conference on Information and Communication Technologies (ICTs) for Development, Education and Training

In a press release, Kennedy Sinkali, surrounded by a crowd of eager fifth-grade school children, is captured explaining phonics to them in front of a laptop screen. Sinkali is a teacher in a village near Ndola in the Copperbelt province of Zambia and uses the school’s only computer, which has to be shared between four classes and three hundred children.

Natasha Bomba, who took the picture while volunteering at the school, was announced as the winner of the first eLearning Africa photo competition. The prize, a digital camera, will be presented during the eLearning Africa conference from May 26th – 28th in Lusaka, Zambia.

The photo which takes the first runner-up prize was taken in Cameroon by Jenny Sanborn from HITIP, a non-profit, community-based organisation. She photographed Karine, a survivor of polio who lives in Douala. Rather than begging, she sells phone credit to make her living.

Mary Ann Hood from South Africa took the picture which was announced by the jury as second runner-up. It shows six-year-old Thandi from Uganda followed by her friends, taking pictures with a mobile phone camera.

To view the top ten entries and the audience favourite, go to
www.elearning-africa.com/picturevoting_home.php

The ten best photos and the audience favourite will be featured in an exhibition at the eLearning Africa conference.

eLearning Africa launched the online photo contest in the run-up to this year’s conference to find out how ICTs have changed lives in Africa. The organisers invited people from Africa to submit images that show how they live, learn and work with ICTs.

eLearning Africa is the key networking event for investors, education experts, as well as providers of education and training on the continent. More information can be found at www.elearning-africa.com

The top three photos can be downloaded at: http://www.elearning-africa.com/pdf/press/eLA2010_PhotoCompetition_Top_three_photos.zip

Linux is blessed with a variety of methods for accessing, expanding and building dynamic, scalable storage solutions. And they’re not just for industry experts either – even everyday Linux users can get access to a great deal of functionality by sharing and accessing data across a network.

Set up iSCSI and your data will stream from your PC like a magical rainbow. Perhaps. If you’re very lucky.

But there’s a new generation of solutions that can increase performance, offer more features and improve security – one of which is iSCSI. As its name implies, iSCSI is a version of the SCSI protocol, which is responsible for shuffling data between various SCSI devices. The key difference with iSCSI is that instead of transporting data across local cables and buses, the ‘i’ takes that data across the internet or your local network, attaching remote storage devices to your local system. It’s perfect for storage area networks (SANs) in particular, and you’ll find network administrators in enterprises of all sizes singing the praises of iSCSI’s ability to combine big-business fibre channel commands with generic networking hardware, saving their departments thousands of pounds in both hardware and infrastructure costs. iSCSI is also a great general-purpose remote storage solution that could easily replace the NFS protocol.

Understanding iSCSI

You can now find iSCSI in many network-attached storage (NAS) devices for the home and even standard Linux installations. This is because it’s a great storage protocol for an expanding network. It might be hard work to master, but you can build a working configuration with relative ease. The great advantage that iSCSI has over some of the alternatives is that drives are exported as block devices, just as blocks of data would be transported over an old SCSI cable. This means that, to the Linux kernel, these drives are handled exactly like local block devices. This makes it perfect for connecting the storage area of a database to the client application or, more recently, the virtual storage devices used by VMware and VirtualBox virtual machines. It’s also ideal if you want to run a machine without any local storage – traditionally the domain of NFS.

Use ‘apt-get install iscsitarget’ to add the appropriate packages to your installation.

Before getting started, your first step should be to familiarise yourself with some of the concepts that are used by iSCSI. These appear to take their names from the Terminator films, with the two most important being the Initiator and the Target. The Initiator is the iSCSI equivalent of the client. It’s the machine you want to have access to the remote data – the one that’s running the applications, or your desktop. The Target is the place the Initiator grabs the data from – another machine running the iSCSI server software and managing the requests to and from the storage medium. You’ll often find NAS drives running the Target server, for example, and you’ll only need to run the Initiator on your local machine in order to access the Target drive.

Set up the Target

It’s possible to share a large variety of different storage types over iSCSI, but the easiest to configure are entire drives. iSCSI connects devices at the block level, which means the job of partitioning and formatting can be left to the Initiator rather than the machine that’s attached directly to the hard drive. On our system, the drive we used was listed as /dev/sdb, and we’ll stick with this example throughout this tutorial. The system drive is normally /dev/sda. To find out what yours is, type fdisk -l on the command line for an overview of what’s connected to your system.

Edit the configuration file in nano. You’ll need to add a line which ensures iSCSI is switched on.

On the Target machine, you first need to install the ‘iscsitarget’ package. You can do this either from the Synaptic package manager or by typing sudo apt-get install iscsitarget on the command line. This will also install several configuration files, and the first of these that we need to look at is ‘/etc/default/iscsitarget’. You can type sudo nano followed by the path to the file name to edit it on the command line, or use your favourite desktop editor if you prefer. We only need to make a single edit here – making sure ‘ISCSITARGET_ENABLE=true’ is the only line in the file. Nano users need to press [Ctrl]+[X], then [Y] to save the changes.

Edit configuration files

The next file we need to edit is ‘/etc/ietd.conf’, which you’ll need to open in an editor. This document contains a working configuration, with lines using the # symbol designated as comments and therefore out of action.

The first line we need to edit defines what’s known as the iSCSI qualified name, or IQN for short. Just search for Target, followed by iqn. As with pages on the net, this IQN name has to be unique to your installation, and it takes the form of ‘iqn’, followed by the year and month, then a reversed version of your domain name. This is then followed by a colon and a reference to whatever you’re going to call the target storage device. This can be anything you like. Here’s what we chose:

iqn.2010-01.com.example:storage.disk2

Next, we need to define the drive that’s going to be shared over iSCSI. Remove the # symbol from the line starting with ‘Lun’ and modify it to read Lun 0 Path=/dev/sdb,Type=fileio. You need to change ‘/dev/sdb’ to the location of the drive that you’ve decided to share. Next, uncomment the Alias line at the bottom of the current section and save the file.

You’ll need to do some deeper editing to the ‘/etc/ietd.conf’ file.

You may have noticed that there are two lines available for a username and password, but we’re going to leave these untouched for now because we’re running our iSCSI device over a trusted network. You can always come back to this point and change the configuration after you’ve got the basic connection working, if you think that you need to.

To enable the device to be shared, open ‘/etc/initiators.allow’ and add iqn.2010-01.com.example:storage.disk2 ALL. When you get the connection working, you’ll need to change ‘ALL’ to the IP address of the machines allowed to access your iSCSI device, but for now we’re trying to remove all obstacles that could stop us getting the connection working. Start the Target server by typing sudo /etc/init.d/iscsitarget start.

Set up the Initiator

It’s now the turn of the other machine, the Initiator. To begin, you need to install the ‘open-iscsi’ package. Once that’s done, open the ‘/etc/iscsi/iscsid.conf’ configuration file and look for the line starting with ‘node.startup’. Change the default value of ‘manual’ to automatic, save the file and restart the service by typing sudo /etc/init.d/open-iscsi restart.

Make sure you change the node startup option to ‘manual’.

Almost everything is now configured and ready to go. Our next step is to probe the Target machine to see what storage services it offers, hopefully listing our drive in the process. Type iscsiadm -m discovery -t st -p, followed by the IP address of the Target. You can find this by typing ipconfig on the Target machine. If everything is set up correctly, you should see the IQN of your drive as output to the iscsiadm. This is the output we received:

iscsiadm -m discovery -t st -p 192.168.1.61
192.168.1.61:3260,1 iqn.2010-01.com.example:storage.disk2

Now you know that the Target machine is correctly configured and that iSCSI can see the remote storage device, you need to type iscsiadm -m node. This will automatically create configuration files within /var/lib/iscsi/nodes for the storage unit on your local machine, which will allow the Initiator to mount the device automatically when the service is restarted. You may need to do this manually by typing sudo /etc/init.d/open-iscsi restart.

The remote drive should now be mounted locally. The best way to check is to type fdisk -l to list all the storage devices attached to your machine. The iSCSI drive should be part of the output, but you won’t see any indication that it’s being connected over a network. That’s the great advantage of using iSCSI.

Mount the drive

iSCSI passes the block information, so you need to format the remote drive from the Initiator machine before it can be used. This process is exactly the same as partitioning and formatting any other drive on your system. You could use fdisk on the command line, for example, or you could take the easy route and use a graphical partitioning tool like GParted, which you can install through your distro’s package manager.

After launching GParted, you first need to select the remote drive from the dropdown list in the top-right of the main window. As with fdisk, the iSCSI drive looks exactly like a local drive, so you need to take special care to select the correct device. You can lose data from other drives permanently with GParted, so proceed with caution.

If you’re hooked up to your target drive you should be able to treat it like any locally connected module – including partitioning it.

With the remote drive selected, click on the large grey area in the middle of the window marked ‘unallocated’. This is the unpartitioned area on your remote drive. Click on ‘New’. By default GParted will use the entire disk, but you’re free to subdivide the remote drive in exactly the same way you would a local one if you prefer. Leave ‘Primary Partition’ selected, then select ‘ext4’ as the filesystem and give your drive a meaningful label before clicking ‘Add’. Click on ‘Apply’ to make the changes to the remote drive, and then simply sit back and wait while the formatting process finishes.

Now that the drive is correctly formatted and partitioned, it’s time to mount it onto the local filesystem so you can start reading and writing data to it. You can use the ‘mount’ command to attach the drive just as you would any other, but there’s one small difference that you have to consider whenever you use multiple iSCSI devices – they might not always have the same /dev path. The solution is to navigate to the device using the /dev/disk/by-path/ nodes, so you can be sure you’re getting the same disk every time.

If you type ls /dev/disk/by-path, for example, you can easily see which devices are using the IQN address. In our example, we mounted the remote drive onto the local /mnt/iscsi folder with the following commands:

mkdir /mnt/iscsi
mount /dev/disk/by-path/ip-192.168.1.61\:3260-iscsi-iqn.2010-01.com.example\:storage.disk2-lun-0-part1 /mnt/iscsi

You can now read and write files to the /mnt/iscsi mount point, and these are passed directly to the remote drive just as if they were connected using an extremely long SCSI cable.

iSCSI on NAS boxes

Two of the trickiest parts of using iSCSI are finding the hardware and configuring the Target machine, but luckily there may be another option if you have a Linux-based network-attached storage box. Many of these will offer up a chunk of the storage inside the box over an iSCSI connection, and you can usually activate and configure this facility with just a couple of clicks. Some of these will let multiple Initiators access a single target and enable you to add CHAP password authentication. Then it’s simply a case of running the iSCSI discovery procedure on your Initiator hardware. If you’ve chosen to use a password and username, you’ll need to run the ‘iscsiadm’ command on the Initiator to add those values to the configuration file for that Target. The command takes the following format:

iscsiadm -m node --targetname IQN --portal IP AND PORT OF TARGET --op=update --name node.session.auth.

You need to run this three times, changing the end parameters each time. With the first execution, add authmethod –value=CHAP to the authentication check. For the second, add username –value=username to specify the username for the connection, and for the third execution add password –value=password to specify the password.

Create a virtual hard drive

Many more technical distributions, such as Fedora, use logical volume management (LVM) for local storage and filesystems. One of the advantages of LVM is that you can shrink, expand and create partitions on the fly from the pool of storage on your machine. Logical volumes can be used for all sorts of tasks. Virtual machines often use them to keep data from the main system, and they’re handy if you enjoy playing with filesystems. They’re also useful if you want to try iSCSI, because you don’t need to have a spare hard drive – you just need the space within your logical volume pool.

The key to adding new virtual drives is the ‘lvcreate’ command. We used the following command to create a 10GB logical volume: lvcreate -L10G -n vdrive vg. This creates a volume called ‘vdrive’ in a volume group called ‘vg’. You’ll need to take a look in your /dev directory to discover the name of the logical volume group used by your installation. After creating the drive, it appears in the /dev volume tree just like any other device and you can share it across the iSCSI connection like a real hard drive.

Even without LVM, there are other options for dynamically shared storage. You could create an image file, for example, by typing dd if=/dev/zero of=/mnt/iscsi.img bs=1024k count=1000. The ‘count’ value is the size of the image, while ‘/mnt/iscsi.img’ is the file that’s created. You can use that path as the source for the iSCSI Target on the ‘Lun 0’ line in the ‘/etc/ietd.conf’ configuration file, and use it like a real partition.

Virtualisation

iSCSI is commonly used by cloud applications and the world of virtualisation. This is so you can access the same hard drive data regardless of where the virtual machine is running. If you’re in the market for a major, enterprise-grade virtualisation solution that uses iSCSI, take a look at VMware’s ESXi solution, which is available for free from www.vmware.com.

Boot options

If you want the Target iSCSI device to be available each time you boot the Initiator machine, you will need to add the remote device to the ‘/etc/fstab’ file. The quickest way to do this is to copy another line in the file and change the parameters to suit the iSCSI device. Make sure the path uses the ‘by-name’ format so that you can be sure you get the same drive at each boot.