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Today, email is an important part of many people's life. As there are
many options as to how to set it up, and as having it set up correctly is
important for some Ubuntu utilities, we will try to cover the basics in
this section.
There are three main functions that make up an e-mail system. First there is
the Mail User Agent (MUA) which is the program a user
actually uses to compose and read mails. Then there is the Mail
Transfer Agent (MTA) that takes care of transferring messages
from one computer to another. And last there is the Mail
Delivery Agent (MDA) that takes care of delivering incoming mail
to the user's inbox.
These three functions can be performed by separate programs, but they can
also be combined in one or two programs. It is also possible to have
different programs handle these functions for different types of mail.
On Linux and Unix systems mutt is historically a very
popular MUA. Like most traditional Linux programs it is text based. It is
often used in combination with exim or
sendmail as MTA and procmail as MDA.
With the increasing popularity of graphical desktop systems, the use of
graphical e-mail programs like GNOME's evolution,
KDE's kmail or Mozilla's thunderbird
is becoming more popular. These programs combine the function
of a MUA, MTA and MDA, but can — and often are — also be used
in combination with the traditional Linux tools.
... Read more »
If you need information about a particular program, you should first
try man program, or
info program.
There is lots of useful documentation in
/usr/share/doc as well. In particular,
/usr/share/doc/HOWTO and
/usr/share/doc/FAQ contain lots of interesting
information. To submit bugs, look at
/usr/share/doc/debian/bug*. To read about
Debian/Ubuntu-specific issues for particular programs, look at
/usr/share/doc/(package name)/README.Debian.
Ubuntu is a little different from other distributions. Even if you're
familiar with Linux in other distributions, there are things you
should know about Ubuntu to help you to keep your system in a good,
clean state. This chapter contains material to help you get oriented;
it is not intended to be a tutorial for how to use Ubuntu, but just a
very brief glimpse of the system for the very rushed.
Ubuntu Packaging System
The most important concept to grasp is the Ubuntu packaging system, which
may be familiar to those who have already used Debian GNU/Linux.
In essence, large parts of your system should be considered under the
control of the packaging system. These include:
/usr (excluding /usr/local)
/var (you could make
/var/local and be safe in there)
/bin
/sbin
/lib
For instance, if you replace /usr/bin/perl, that
will work, but then if you upgrade your perl
package, the file you put there will be replaced. Experts can get
around this by putting packages on "hold” in
aptitude.
One of the best installation methods is apt. You can use the command
line version apt-get, the full-screen text version
aptitude, or the graphical version
synaptic. Note apt will also let you merge
main, contrib, and non-free so you can have export-restricted packages
as well as standard versions.
... Read more »
If you are new to Unix, you probably should go out and buy some books
and do some reading. A lot of valuable information can also be found
in the Debian Reference.
This list of Unix FAQs contains a
number of UseNet documents which provide a nice historical reference.
Linux is an implementation of Unix. The
Linux Documentation Project (LDP)
collects a number of HOWTOs and online books
relating to Linux. Most of these documents can be installed locally;
just install the doc-linux-html package (HTML
versions) or the doc-linux-text package (ASCII
versions), then look in /usr/share/doc/HOWTO.
International versions of the LDP HOWTOs are also available as Ubuntu
packages.
To shut down a running Linux system, you must not reboot with the
reset switch on the front or back of your computer, or just turn off
the computer. Linux should be shut down in a controlled manner,
otherwise files might get lost and/or disk damage might occur. If you run a
desktop environment, there is usually an option to "log out”
available from the application menu that allows you to shutdown (or reboot)
the system.
Alternatively you can press the key combination Ctrl+Alt+Del
. A last option is to log in as root and type one of the
commands poweroff, halt or
shutdown -h now if either of the key combinations do not
work or you prefer to type commands; use reboot to reboot
the system.
Once your system boots, you'll be presented with the login
prompt. Log in using the personal login and password you
selected during the installation process. Your system is now ready for use.
If you are a new user, you may want to explore the documentation which
is already installed on your system as you start to use it. There are
currently several documentation systems, work is proceeding on
integrating the different types of documentation. Here are a few
starting points.
Documentation accompanying programs you have installed can be found in
/usr/share/doc/, under a subdirectory named after the
program (or, more precise, the Debian package that contains the program).
However, more extensive documentation is often packaged separately in
special documentation packages that are mostly not installed by default.
For example, documentation about the package management tool
apt can be found in the packages
apt-doc or apt-howto.
In addition, there are some special folders within the
/usr/share/doc/ hierarchy. Linux HOWTOs are
installed in .gz (compressed) format, in
/usr/share/doc/HOWTO/en-txt/. After installing
dhelp, you will find a browsable index of
documentation in /usr/share/doc/HTML/index.html.
... Read more »
If you created encrypted volumes during the installation and assigned
them mount points, you will be asked to enter the passphrase for each
of these volumes during the boot. The actual procedure differs
slightly between dm-crypt and loop-AES.
dm-crypt
For partitions encrypted using dm-crypt you will be shown the following
prompt during the boot:
Starting early crypto disks... part_crypt(starting)
Enter LUKS passphrase:
In the first line of the prompt, part is the
name of the underlying partition, e.g. sda2 or md0.
You are now probably wondering
for which volume you are actually entering the
passphrase. Does it relate to your /home? Or to
/var? Of course, if you have just one encrypted
volume, this is easy and you can just enter the passphrase you used
when setting up this volume. If you set up more than one encrypted
volume during the installation, the notes you wrote down as the last
step in the section called "Configuring Encrypted Volumes” come in handy. If you did not
make a note of the mapping between
part_crypt and the mount
points before, you can still find it
in /etc/crypttab
and /etc/fstab of your new system.
The prompt may look somewhat different when an encrypted root file system is
mounted. This depends on which initramfs generator was used to generate the
initrd used to boot the system. The example below is for an initrd generated
using initramfs-tools:
No characters (even asterisks) will be shown while entering the passphrase.
If you enter the wrong passphrase, you have two more tries to correct it.
After the third try the boot process will skip this volume and continue to
mount the next filesystem. Please see the section called "Troubleshooting”
for further information.
After entering all passphrases the boot should continue as usual.
... Read more »
Your system's first boot on its own power is what electrical engineers
call the "smoke test”.
If you did a default installation, the first thing you should see when you
boot the system is the menu of the grub or possibly
the lilo bootloader.
The first choices in the menu will be for your new Ubuntu system. If you
had any other operating systems on your computer (like Windows) that were
detected by the installation system, those will be listed lower down in the
menu.
If the system fails to start up correctly, don't panic. If the installation
was successful, chances are good that there is only a relatively minor
problem that is preventing the system from booting Ubuntu. In most cases
such problems can be fixed without having to repeat the installation.
One available option to fix boot problems is to use the installer's
built-in rescue mode (see the section called "Recovering a Broken System”).
If you had any other operating systems on your computer that were not detected
or not detected correctly, please file an installation report.
As described in the section called "Devices Requiring Firmware”, some devices require
firmware to be loaded. In most cases the device will not work at all
if the firmware is not available; sometimes basic functionality is not
impaired if it is missing and the firmware is only needed to enable
additional features.
If a device driver requests firmware that is not available, debian-installer will
display a dialog offering to load the missing firmware. If this option
is selected, debian-installer will scan available devices for either loose firmware
files or packages containing firmware. If found, the firmware will be
copied to the correct location (/lib/firmware) and
the driver module will be reloaded.
Which devices are scanned and which file systems are supported depends on
the architecture, the installation method and the stage of the installation.
Especially during the early stages of the installation, loading the firmware
is most likely to succeed from a FAT-formatted floppy disk or USB stick.
On i386 and amd64 firmware can also be loaded from an
MMC or SD card.
Note that it is possible to skip loading the firmware if you know the
device will also function without it, or if the device is not needed during
the installation.
Support for loading firmware is still relatively basic and is likely to
be improved in future releases of the installer. Currently debian-installer will
for example not display any warning if you choose to load missing firmware,
but the requested firmware is not found.
Please report any issues you encounter by filing an installation report
(see the section called "Submitting Installation Reports”).
Preparing a medium
Although in some cases the firmware can also be loaded from a partition on
a hard disk, the most common method to load firmware will be from some
removable medium such as a floppy disk or a USB stick.
The firmware files or packages must be placed in either the root directory
or a directory named /firmware of the file system on
the medium. The recommended file system to use is FAT as that is most
certain to be supported during the early stages of the installation.
Tarballs containing current packages for the most common firmware are
available from:
Just download the tarball for the correct release and unpack it to the file
system on the medium.
If the firmware you need is not included in the tarball, you can also
download specific firmware packages from the (non-free section of the)
archive. The following overview should list most available firmware
packages but is not guaranteed to be complete and may also contain
non-firmware packages:
It is also possible to copy individual firmware files to the medium. Loose
firmware could be obtained for example from an already installed system or
from a hardware vendor.
... Read more »
Here is a list of installer components with a brief description
of each component's purpose. Details you might need to know about
using a particular component are in the section called "Using Individual Components”.
main-menu
Shows the list of components to the user during installer operation,
and starts a component when it is selected. Main-menu's
questions are set to priority medium, so if your priority is set to
high or critical (high is the default), you will not see the menu. On
the other hand, if there is an error which requires your intervention,
the question priority may be downgraded temporarily to allow you
to resolve the problem, and in that case the menu may appear.
You can get to the main menu by selecting the Go Back button
repeatedly to back all the way out of the currently running component.
... Read more »
![[Note]](https://help.ubuntu.com/10.10/libs/admon/note.png)
![[Warning]](https://help.ubuntu.com/10.10/libs/admon/warning.png)