Assessment</ulink>.</para></listitem>
<listitem><para>The boot manager optionally reads a random seed from the ESP partition, combines it
- with a 'system token' stored in a persistant EFI variable and derives a random seed to use by the OS as
- entropy pool initializaton, providing a full entropy pool during early boot.</para></listitem>
+ with a 'system token' stored in a persistent EFI variable and derives a random seed to use by the OS as
+ entropy pool initialization, providing a full entropy pool during early boot.</para></listitem>
</itemizedlist>
<para><citerefentry><refentrytitle>bootctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
<varlistentry>
<term><keycap>↵</keycap> (Enter)</term>
+ <term><keycap>→</keycap> (Right)</term>
<listitem><para>Boot selected entry</para></listitem>
</varlistentry>
<varlistentry>
<term><keycap>h</keycap></term>
<term><keycap>?</keycap></term>
+ <term><keycap>F1</keycap></term>
<listitem><para>Show a help screen</para></listitem>
</varlistentry>
</varlistentry>
</variablelist>
- <para>The following keys may be used during bootup or in the boot menu to
- directly boot a specific entry:</para>
+ <para>The following keys may be pressed during bootup or in the boot menu to directly boot a specific
+ entry:</para>
<variablelist>
<varlistentry>
</varlistentry>
</variablelist>
+ <para>The boot menu is shown when a non-zero menu timeout has been configured. If the menu timeout has
+ been set to zero, it is sufficient to press any key — before the boot loader initializes — to bring up
+ the boot menu, except for the keys listed immediately above as they directly boot into the selected boot
+ menu item. Note that depending on the firmware implementation the time window where key presses are
+ accepted before the boot loader initializes might be short. If the window is missed, reboot and try
+ again, possibly pressing a suitable key (e.g. the space bar) continuously; on most systems it should be
+ possible to hit the time window after a few attempts. To avoid this problem, consider setting a non-zero
+ timeout, thus showing the boot menu unconditionally. Some desktop environments might offer an option to
+ directly boot into the boot menu, to avoid the problem altogether. Alternatively, use the command line
+ <command>systemctl reboot --boot-loader-menu=0</command> from the shell.</para>
+
<para>In the editor, most keys simply insert themselves, but the following keys
may be used to perform additional actions:</para>
is maintained persistently, while <varname>LoaderConfigTimeoutOneShot</varname> is a one-time override which is
read once (in which case it takes precedence over <varname>LoaderConfigTimeout</varname>) and then
removed. <varname>LoaderConfigTimeout</varname> may be manipulated with the
- <keycap>t</keycap>/<keycap>T</keycap> keys, see above.)</para></listitem>
+ <keycap>t</keycap>/<keycap>T</keycap> keys, see above.</para></listitem>
</varlistentry>
<varlistentry>
boots. <citerefentry><refentrytitle>bootctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>'s
<option>set-default</option> and <option>set-oneshot</option> commands make use of these variables. The boot
loader modifies <varname>LoaderEntryDefault</varname> on request, when the <keycap>d</keycap> key is used, see
- above.)</para></listitem>
+ above.</para></listitem>
</varlistentry>
<varlistentry>
"golden" OS image — i.e. containing the same random seed file in the ESP — will still pass a
different random seed to the OS. It is made sure the random seed stored in the ESP is fully
overwritten before the OS is booted, to ensure different random seed data is used between subsequent
- boots.</para></listitem>
+ boots.</para>
+
+ <para>See <ulink url="https://systemd.io/RANDOM_SEEDS">Random Seeds</ulink> for
+ further information.</para></listitem>
</varlistentry>
<varlistentry>
<term><varname>LoaderSystemToken</varname></term>
- <listitem><para>A binary random data field, that is used for generating the random see to pass to the
- OS (see above). Note that this random data is generally only generated once, during OS installation,
- and is then never updated again.</para></listitem>
+ <listitem><para>A binary random data field, that is used for generating the random seed to pass to
+ the OS (see above). Note that this random data is generally only generated once, during OS
+ installation, and is then never updated again.</para></listitem>
</varlistentry>
</variablelist>
considered 'good' from then on.</para>
<para>The boot menu takes the 'tries left' counter into account when sorting the menu entries: entries in 'bad'
- state are ordered at the end of the list, and entries in 'good' or 'indeterminate' at the beginning. The user can
+ state are ordered at the beginning of the list, and entries in 'good' or 'indeterminate' at the end. The user can
freely choose to boot any entry of the menu, including those already marked 'bad'. If the menu entry to boot is
- automatically determined, this means that 'good' or 'indeterminate' entries are generally preferred (as the top item of
- the menu is the one booted by default), and 'bad' entries will only be considered if there are no 'good' or
+ automatically determined, this means that 'good' or 'indeterminate' entries are generally preferred (as the bottom
+ item of the menu is the one booted by default), and 'bad' entries will only be considered if there are no 'good' or
'indeterminate' entries left.</para>
<para>The <citerefentry><refentrytitle>kernel-install</refentrytitle><manvolnum>8</manvolnum></citerefentry> kernel
projects / thirdparty / systemd.git / blobdiff