X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=man%2Fsystemd-nspawn.xml;h=fdb0c298b0aef7a37bd2ea49a579a47135afb70a;hb=b98b483bac585af754e8a22ea890db8486905d8a;hp=b66c34df01fea0dec00f6ef61b5dce04057f2f7f;hpb=ec16945ebfe64d5cd5403ae1a1b16bc05a779a16;p=elogind.git

diff --git a/man/systemd-nspawn.xml b/man/systemd-nspawn.xml
index b66c34df0..fdb0c298b 100644
--- a/man/systemd-nspawn.xml
+++ b/man/systemd-nspawn.xml
@@ -231,8 +231,10 @@
                                 its root directory (as configured with
                                 <option>--directory=</option>), that
                                 is removed immediately when the
-                                container terminates. May not be
-                                specified together with
+                                container terminates. This option is
+                                only supported if the root file system
+                                is <literal>btrfs</literal>. May not
+                                be specified together with
                                 <option>--image=</option> or
                                 <option>--template=</option>.</para></listitem>
                         </varlistentry>
@@ -303,13 +305,22 @@
 
                                 <listitem><para>Sets the machine name
                                 for this container. This name may be
-                                used to identify this container on the
-                                host, and is used to initialize the
-                                container's hostname (which the
-                                container can choose to override,
-                                however). If not specified, the last
-                                component of the root directory of the
-                                container is used.</para></listitem>
+                                used to identify this container during
+                                its runtime (for example in tools like
+                                <citerefentry><refentrytitle>machinectl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
+                                and similar), and is used to
+                                initialize the container's hostname
+                                (which the container can choose to
+                                override, however). If not specified,
+                                the last component of the root
+                                directory path of the container is
+                                used, possibly suffixed with a random
+                                identifier in case
+                                <option>--ephemeral</option> mode is
+                                selected. If the root directory
+                                selected is the host's root directory
+                                the host's hostname is used as default
+                                instead.</para></listitem>
                         </varlistentry>
 
                         <varlistentry>
@@ -769,7 +780,7 @@
                 <example>
                         <title>Boot a minimal Fedora distribution in a container</title>
 
-                        <programlisting># yum -y --releasever=19 --nogpg --installroot=/srv/mycontainer --disablerepo='*' --enablerepo=fedora install systemd passwd yum fedora-release vim-minimal
+                        <programlisting># yum -y --releasever=21 --nogpg --installroot=/srv/mycontainer --disablerepo='*' --enablerepo=fedora install systemd passwd yum fedora-release vim-minimal
 # systemd-nspawn -bD /srv/mycontainer</programlisting>
 
                         <para>This installs a minimal Fedora distribution into
@@ -814,13 +825,16 @@
                 </example>
 
                 <example>
-                        <title>Boot into a <literal>btrfs</literal> snapshot of the host system</title>
+                        <title>Boot into an ephemeral <literal>btrfs</literal> snapshot of the host system</title>
 
-                        <programlisting># btrfs subvolume snapshot / /.tmp
-# systemd-nspawn --private-network -D /.tmp -b</programlisting>
+                        <programlisting># systemd-nspawn -D / -xb</programlisting>
 
                         <para>This runs a copy of the host system in a
-                        <literal>btrfs</literal> snapshot.</para>
+                        <literal>btrfs</literal> snapshot which is
+                        removed immediately when the container
+                        exits. All file system changes made during
+                        runtime will be lost on shutdown,
+                        hence.</para>
                 </example>
 
                 <example>
@@ -847,7 +861,8 @@
                         <citerefentry project='die-net'><refentrytitle>debootstrap</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
                         <citerefentry project='archlinux'><refentrytitle>pacman</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
                         <citerefentry><refentrytitle>systemd.slice</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
-                        <citerefentry><refentrytitle>machinectl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
+                        <citerefentry><refentrytitle>machinectl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+                        <citerefentry><refentrytitle>btrfs</refentrytitle><manvolnum>8</manvolnum></citerefentry>
                 </para>
         </refsect1>