user_guide.tex

TTYLINUX迷你代码 TTYLINUX迷你代码

Note that depending on the BIOS, it might not be possible to boot
from anything but the first two hard disks installed in the
system.

What to do if your target disk is not partitioned yet? ttylinux
includes the \url{fdisk} program that can be used to partition
hard disks. For example, to partition a hard disk connected
as master to the first IDE controller, use:

\begin{lstlisting}
  fdisk /dev/hda
\end{lstlisting}

The user interface of {\tt fdisk} is somewhat primitive, so be
careful. If you haven't used it before, a good idea would be
to search the Internet for instructions. The basic commands
you may need are "d" to delete a partition, "n" to create a
new partition, "p" to print the current partition table, and
"w" to write the edited partition table to disk. You can also
use "q" to exit {\tt fdisk} without saving your changes.


\subsubsection{Boot loader location}

You can install the LILO boot loader in one of two places: either
into the master boot record (MBR) of the hard disk you are installing
to or into the boot sector of the partition you are installing to.

With LILO installed in the MBR of your first hard disk, it will take
over the boot process of your computer completely. If you have other
operating systems installed on the computer, you will need to add
them to the LILO configuration file (\url{/etc/lilo.conf}) in
ttylinux to be able to boot into them.

With LILO installed in the boot sector of the target partition
or in the MBR of a hard disk other than the first one in your
computer, you will need to have another boot loader installed in
the MBR of your first hard disk. You have to add the MBR or
boot sector where the ttylinux LILO is installed to the setup
of that boot loader in order to be able to boot ttylinux.


\subsubsection{Running the installer}

Once you have decided on target device and boot loader location,
you can run the installer. The script is called \url{installer}
and can be invoked as follows (the square brackets indicate
an optional parameter):

\begin{lstlisting}
  installer [mbr] source-device target-device
\end{lstlisting}

For example, to install from the CD-ROM device {\tt /dev/hdc}
onto the partition {\tt /dev/hda2}, placing LILO into the MBR
of the {\tt /dev/hda} hard disk, you would use:

\begin{lstlisting}
  installer mbr /dev/hdc /dev/hda2
\end{lstlisting}

Another example, installing from the second SATA CD-ROM
device {\tt /dev/scd1} onto the third partition of the second
SATA hard disk, placing LILO in the boot sector of the
target partition:

\begin{lstlisting}
  installer /dev/scd1 /dev/sdb3
\end{lstlisting}

The installer will check if your source device contains a
ttylinux CD-ROM before proceeeding. If the CD-ROM is found,
a summary of what is going to be installed where is printed
and you are given a last chance of aborting the whole
install. Enter "yes" to continue the installation or anything
else to abort.

The installer creates an ext2 filesystem on the target
partition, then copies the distribution files onto the
new filesystem, and finally installs the LILO bootloader.

Once the installer is finished, it prints out a success
message. At this point you can remove the CD-ROM from your
computer and reboot.



\subsection{Customization}
\label{customize}

The following instructions are mainly useful for installing
ttylinux by hand, but the configuration files and options
described here are also present in a ttylinux system
installed from the bootable CD-ROM.

Before you go about installing ttylinux, you may want to change a
few settings inside the image file to fit your own system. This is
done by uncompressing and mounting the image and then making the
appropriate changes. If the image is in the current working directory,
do the following as the \url{root} user:

\begin{lstlisting}
  gunzip rootfs.gz
  mkdir mnt
  mount -o loop rootfs mnt
\end{lstlisting}
       
Now the ttylinux filesystem is mounted on the directory \url{mnt}. Take a
look at it if you wish. If you want to install ttylinux to a hard
disk by hand, you can now create an installation archive for that
purpose as follows:

\begin{lstlisting}
  cd mnt
  tar cvzf ../ttylinux-hd.tar.gz .
  cd ..
\end{lstlisting}
       
After this, you have a file called \url{ttylinux-hd.tar.gz} that can be
unpacked onto any filesystem you like.
     
The things you will probably want to customize on ttylinux are the
keyboard map and timezone in use and the Internet provider settings.
You can copy over the keyboard and timezone setting from your working
system as follows:

\begin{lstlisting}
  mnt/bin/dumpkmap > mnt/etc/i18n/keymap.dat
  cat /etc/localtime > mnt/etc/localtime
\end{lstlisting}
       
To set up the dial information for an Internet provider, you need to
know the following:

\begin{itemize}     
\item the device your modem is connected to, i.e. {\tt /dev/ttyS1}
\item the init string for your modem, i.e. {\tt ATZ}
\item the speed your modem can talk to the computer, i.e. {\tt 115200}
\item the phone number of your ISP, i.e. {\tt 1-800-LETMEIN}
\item your user name at the ISP, i.e. {\tt joeuser}
\item your password at the ISP, i.e. {\tt joepass}
\end{itemize}

The above is for dialup using a modem. If you want to use ISDN dialup,
you need to know the following:

\begin{itemize} 
\item the phone number of your ISP, i.e. {\tt 1-800-12345678}
\item your user name at the ISP, i.e. {\tt joeuser}
\item your password at the ISP, i.e. {\tt joepass}
\item the phone number you want to use for dialing out
\item whether you want to use automatic or manual dialing
\end{itemize}

Edit the file \url{mnt/etc/isp.conf} and change the settings there to
your liking. Note that ttylinux only knows about providers that
launch a PPP session immediately after dialup (which should be true
for almost all providers these days), so if some special
procedure is needed to log you in, your Internet connection will not
work with ttylinux. The ttylinux approach will work with almost all
providers in Germany, but I don't know about other countries.

For ttylinux to use ISDN, you need to have \url{USE_ISDN=yes}
in \url{/etc/isp.conf}, the default is not to use ISDN. Obviously, you
also need a kernel with ISDN support and hardware support for your ISDN
hardware. If you need kernel modules to run your ISDN hardware, you
will also need to add those and a suitable \url{/etc/modules.conf} to 
the ttylinux filesystem.

Once you are finished making changes, unmount the filesystem and  run
\url{gzip} to compress it again:

\begin{lstlisting}
  umount mnt
  gzip -9 rootfs
\end{lstlisting}
       
You are now ready for the real installation.
    
Note that this section has only covered the minimum customization
needed to run ttylinux. There is more to tune, have a look at the
system guide (section \ref{sysguide}) below for information. If you aim
at the approach of running ttylinux from ramdisk, you must
configure everything for your needs before you continue the installation,
so it may be a wise idea to read the system guide section before you
countinue. If you install to a hard disk, you can always configure
things later.
     

\subsection{Installation by hand}
  
I am assuming that you use \url{LILO} (short for Linux Loader) as your
boot loader. You can also use others like \url{loadlin}, but you will
obviously need some \url{LILO} experience to convert the \url{LILO}
example given here to some other boot manager. I am also assuming
that you want to add ttylinux to an existing LILO setup that is
already used to boot other (Linux) systems on your machine.

If you want to use the \url{syslinux} boot loader to load ttylinux
from a \url{FAT} filesystem, please see the appendix on creating a
bootable CD-ROM (appendix \ref{makecdrom}) for an example.
     
Put the \url{rootfs.gz} image and the Linux kernel you want to use to run
ttylinux into the directory that holds your other boot files, most
likely this will be \url{/boot}. Let us assume your kernel image file is
called \url{bzImage-ttylinux}. You now need to add the following section
to \url{/etc/lilo.conf}:

\begin{lstlisting}
  image=/boot/bzImage-ttylinux
      label=ttylinux
      initrd=/boot/rootfs.gz
      root=/dev/ram0
      read-only
\end{lstlisting}
           
Now rerun the \url{LILO} installer by typing \url{/sbin/lilo}.
On your next boot, you can enter \url{ttylinux} on the \url{LILO} boot
prompt to boot ttylinux. That is all, you are now ready to try ttylinux.

If you want to install onto hard disk, you need to have a partition
of at least 4 megabytes size available. Assuming this partition is
\url{/dev/hda8}, do the following, using the file \url{ttylinux-hd.tar.gz}
obtained above (in section \ref{customize}):

\begin{lstlisting}  
  mke2fs /dev/hda8
  mount -t ext2 /dev/hda8 mnt
  cd mnt
  tar xvzf ../ttylinux-hd.tar.gz
  cd ..
\end{lstlisting}
       
Now do the customization as outlined above. You will also need to
change the root device configured in \url{mnt/etc/fstab}. Once you are
done, you just need to unmount the partition:

\begin{lstlisting}     
  umount mnt
\end{lstlisting}
       
Now you can setup \url{LILO} as explained above, only change the line for
the root filesystem to \url{root=/dev/hda8} and remove the \url{initrd}
line. Ready to go.
     

\section{System guide}
\label{sysguide}
  
This section gives a short overview over the system, its configuration,
and some of the installed programs.


\subsection{Basic Features}
  
On bootup, ttylinux provides 6 text consoles for login. The default
setup has two user accounts: \url{root} (the administrator account)
with password \url{root} and \url{guest} with password \url{guest}.
     
The \url{syslogd} and \url{klog} daemons are running and log kernel
and system messages to the file \url{/var/log/messages}.

If you need a text editor, \url{e3} is installed. Simply invoke it by
typing \url{e3} \url{/path/to/filename}. A help screen is available by
pressing \url{Alt-H}. \url{e3} understands a lot of the old WordStar
commands, so it feels a bit like WordStar, an old Borland IDE, or the
common Linux editor \url{joe}. For those accustomed to different
editors, \url{e3vi} will startup \url{e3} in \url{vi} emulation
mode (\url{e3em} for \url{emacs} emulation mode, \url{e3pi} for
\url{pico} emulation mode).

For manipulation of users, groups and passwords, the tools {\tt passwd},
{\tt adduser}, {\tt addgroup}, {\tt del\-user}, and {\tt delgroup} are
present.

If you have not changed the timezone and keyboard settings as outlined
in the customization section (\ref{customize}, above), ttylinux will use
its default settings. The default timezone is UTC, the default keyboard
mapping is for a US keyboard.

The \url{inetd} super-server and the \url{dropbear} SSH server are
running by default. A telnet server will be forked by \url{inetd} when
a telnet connection comes in.

ttylinux includes a basic packet filtering firewall which is
enabled by default on the dialup interface. Note that the telnet
server is not visible from the external side of the dialup
interface in the default firewall configuration.


\subsection{Bootup and Shutdown}
  
On system bootup, the init process runs the script
\url{/etc/rc.d/rc.sysinit} to get the system up. The script will do the
usual business of checking  and remounting the root filesystem and will
start up basic networking.

After that is done, \url{rc.sysinit} will run all executables from the
directory \url{/etc/rc.d/rc.start}. It does not matter whether these are
scripts or compiled programs. All executables will be passed the
parameter \url{start}. For example, if there is a script called
{\url runme}, \url{rc.sysinit} will execute \url{runme} \url{start}.

The default initscripts that come with ttylinux are stored in the
directory \url{/etc/rc.d/init.d}. Those that need to be run at bootup are
symlinked into the \url{rc.start} directory. If you want to write your own
initscripts, place them in the \url{init.d} directory and place a symlink
in the \url{rc.start} and perhaps also in the \url{rc.stop} directory.

If you don't want to write your own script, you can also add commands
to the file \url{/etc/rc.d/rc.local} - this script will be run at the very
end of the boot process, after all others scripts have run.
     
On shutdown, the script \url{/etc/rc.d/rc.reboot} gets run. This will run
all the programs from the \url{/etc/rc.d/rc.stop} directory, and each program
will be passed a \url{stop} parameter. Our example script called \url{runme}
would be executed as \url{runme} \url{stop}.
     
Both scripts from \url{rc.start} and \url{rc.stop} will be run in ASCII
order. If you need them to run in a specific order, you could for
example use names like \url{01.first} and \url{02.second}. This is how 
the scripts  that come with ttylinux are named. Everything in \url{rc.start}
and \url{rc.stop}  should be a symlink, so you can simply remove that
link if you want to disable a specific script.

Initscripts can also be called manually in case you want to start  or
stop something while the system is running. To make this  easier, a
helper script called \url{service} is provided. For example:

\begin{lstlisting}     
  service inetd stop
\end{lstlisting}
       
will stop the \url{inetd} server daemon. All scripts (except \url{pppconf},
which understands few options) know about the options \url{start},
\url{stop}, and \url{restart} that do the obvious things. Some scripts also
know about \url{status} and \url{reload} for displaying status information
and for reloading service configuration files.

All scripts will print a list of supported options if they are called
with no option present.


\subsection{Using PPP dialup}
  
What to put into \url{/etc/isp.conf} to configure the dailup information
is outlined above in the customization section (\ref{customize}, above).
What you will find here is an overview of how to actually use the PPP
subsystem for Internet dialup.
     
Assuming \url{/etc/isp.conf} was setup correctly before boot, you only 
need one command to start up the Internet connection:

\begin{lstlisting}     
  ppp-up
\end{lstlisting}

If you use ISDN with autodialing enabled (\url{ISDN_MODE=auto}
set in \url{/etc/isp.conf}), you do not need to run \url{ppp-up}. Just
run a program that sends packets to an Internet host.
     
\url{ppp-up} triggers the PPP daemon, which will dial the provider and try
to login. \url{ppp-up} can be run by any user in the \url{ppp} group. In the
default ttylinux configuration, the \url{ppp} group has no members, so only
\url{root} can start and stop the internet connection. You can watch
\url{/var/log/messages} (using \url{tail} \url{-f}) to see when the
connection is up and running. After that, the Internet connection is ready
for use. For example, the SSH server will be reachable from the outside
world.

You can browse the web by using the \url{retawq} web browser. Use the
\url{g} key to enter a URL, then navigate around using the cursor and
return keys. You can leave the browser by pressing \url{Shift-Q}.

If you use ISDN, you can enable and disable channel bundling by
calling the \url{bundle} and \url{unbundle} scripts while the connection
is up. The default for new connections is to always use a single channel,
even if channel bundling was enabled before. To check whether channel
bundling is currently enabled, use the command: