Configuration file syntax is described in section L</"CONFIGURATION
FILES">.
+Novaboot newcomers may be confused by a large number of configuration
+options. Understanding all these options is not always needed,
+depending on the used setup. The L<figure from the doc directory
+|https://github.com/wentasah/novaboot/blob/master/doc/typical-setups.svg>
+shows different setups that vary in how much effort is needed
+configure novaboot for them. The setups are:
+
+=over 3
+
+=item A: Laptop and target device only
+
+This requires to configure everything on the laptop side, including a
+serial line connection (L</--serial>, L</--remote-cmd>, ...), power
+on/off/reset commands (L</--reset-cmd>, ...), TFTP server
+(L</--server>, L</--prefix>...), device IP addresses, etc.
+
+=item B: Laptop, target device and external TFTP server
+
+Like the previous setup, but the TFTP (and maybe DHCP) configuration
+is handled by a server. Novaboot users need to understand where to
+copy their files to the TFTP server (L</--server>) and which IP
+addresses their target will get, but do not need to configure the
+servers themselves.
+
+=item C: Novaboot server running novaboot-shell
+
+With this setup, the configuration is done on the server. Users only
+need to know the SSH account (L</--ssh>) used to communicate between
+novaboot and novaboot server. The server is implemented as a
+restricted shell (L<novaboot-shell(1)>) on the server. No need to give
+full shell access to novaboot users on the server.
+
+=back
+
=head2 Simple examples of using C<novaboot>:
To boot Linux (files F<bzImage> and F<rootfs.cpio> in current
=back
-=head1 PHASES AND OPTIONS
+=head1 OPTIONS AND PHASES
Novaboot performs its work in several phases. Command line options
described bellow influence the execution of each phase or allow their
=item --remote-expect=I<string>
-Wait for reception of I<string> after establishing the remote
-connection. This option is needed when novaboot should wait for
-confirmation before deploying files to the target, e.g. to not
-overwrite other user's files when they are using the target.
+Wait for reception of I<string> after establishing the remote serial
+line connection. Novaboot assumes that after establishing the serial
+line connection, the user running novaboot has exclusive access to the
+target. If establishing of the serial line connection happens
+asynchronously (e.g. running a command remotely via SSH), we need this
+option to wait until the exclusive access is confirmed by the remote
+side.
+
+Depending on target configuration, this option can solve two practical
+problems: 1) Overwriting of files deployed by another user currently
+using the target. 2) Resetting the target board before serial line
+connection is established and thus missing bootloader interaction.
+
+Example of usage with the L<sterm
+tool|https://rtime.felk.cvut.cz/gitweb/sojka/sterm.git>:
+
+ --remote-cmd='ssh -tt example.com sterm -v /dev/ttyUSB0' --remote-expect='sterm: Connected'
=item --remote-expect-silent=I<string>
=item --netif=I<network interface>
-Network interface used to deploy files to the target. The default value is
-I<eth0>. This option influences the configuration of the DHCP server started
-by B<--dhcp-tftp> and the value that B<$NB_MYIP> get replaced with during
-U-Boot conversation.
+Network interface used to deploy files to the target. This option
+influences the configuration of the DHCP server started by
+B<--dhcp-tftp> and the value that B<$NB_MYIP> get replaced with during
+U-Boot conversation. The default value is C<$netif> variable from
+configuration files, which defaults to I<eth0>.
=item --iso[=filename]
Disable U-Boot interaction previously enabled with B<--uboot>.
+=item --uboot-stop-key=I<key>
+
+Character, which is sent as a response to U-Boot's "Hit any key to
+stop autoboot" message. The default value is newline, but some devices
+(e.g. TP-Link TD-W8970) require a specific key to be pressed.
+
=item --uboot-init
Command(s) to send the U-Boot bootloader before loading the images and
=item --exiton-timeout=I<seconds>
By default B<--exiton> waits for the string match forever. When this
-option is specified, "exiton" timeouts after the specifies the number of
+option is specified, "exiton" timeouts after the specified number of
seconds and novaboot returns non-zero exit code.
=item -i, --interactive
(see B<--build-dir>) of the module to load and the remaining words are
passed to it as the command line parameters.
+When booting Linux, the first C<load> line usually refers to the
+kernel image and its command line parameters (unless you use some
+special pre-loader). Other C<load> lines may refer to an initramfs
+image and/or a device tree blob. Their order is not important, as the
+device tree is recognized as the file name ending with C<.dtb>.
+
When the C<load> line ends with "<<WORD" then the subsequent lines
until the line containing solely WORD are copied literally to the file
-named on that line. This is similar to shell's heredoc feature.
+named on that line. This is similar to the heredoc feature of UNIX
+shells.
When the C<load> line ends with "< CMD" then command CMD is executed
with F</bin/sh> and its standard output is stored in the file named on
specified with the B<--target> command line option or
B<NOVABOOT_TARGET> environment variable.
+=item $netif
+
+Default value for the B<--netif> option. If not specified, it defaults
+to I<eth0>.
+
=item %targets
Hash of target definitions to be used with the B<--target> option. The