man: change links to container interface doc to https://systemd.io/

Now that we converted the documentation we should also link to it.

man/systemd-getty-generator.xml

@@ -28,29 +28,20 @@
   <refsect1>
     <title>Description</title>
 
-    <para><filename>systemd-getty-generator</filename> is a generator
+    <para><filename>systemd-getty-generator</filename> is a generator that automatically instantiates
-    that automatically instantiates
+    <filename>serial-getty@.service</filename> on the kernel console(s), if they can function as ttys and are
-    <filename>serial-getty@.service</filename> on the kernel
+    not provided by the virtual console subsystem. It will also instantiate
-    console(s), if they can function as ttys and are not provided by
+    <filename>serial-getty@.service</filename> instances for virtualizer consoles, if execution in a
-    the virtual console subsystem. It will also instantiate
+    virtualized environment is detected. If execution in a container environment is detected, it will instead
-    <filename>serial-getty@.service</filename> instances for
+    enable <filename>console-getty.service</filename> for <filename>/dev/console</filename>, and
-    virtualizer consoles, if execution in a virtualized environment is
+    <filename>container-getty@.service</filename> instances for additional container pseudo TTYs as requested
-    detected. If execution in a container environment is detected, it
+    by the container manager (see <ulink url="https://systemd.io/CONTAINER_INTERFACE"><filename>Container
-    will instead enable <filename>console-getty.service</filename> for
+    Interface</filename></ulink>). This should ensure that the user is shown a login prompt at the right
-    <filename>/dev/console</filename>, and
+    place, regardless of which environment the system is started in. For example, it is sufficient to
-    <filename>container-getty@.service</filename> instances for
+    redirect the kernel console with a kernel command line argument such as <varname>console=</varname> to
-    additional container pseudo TTYs as requested by the container
+    get both kernel messages and a getty prompt on a serial TTY. See <ulink
-    manager (see <ulink
-    url="https://www.freedesktop.org/wiki/Software/systemd/ContainerInterface/"><filename>Container
-    Interface</filename></ulink>). This should ensure that the user is
-    shown a login prompt at the right place, regardless of which
-    environment the system is started in. For example, it is
-    sufficient to redirect the kernel console with a kernel command
-    line argument such as <varname>console=</varname> to get both
-    kernel messages and a getty prompt on a serial TTY. See <ulink
     url="https://www.kernel.org/doc/Documentation/admin-guide/kernel-parameters.txt"><filename>kernel-parameters.txt</filename></ulink>
-    for more information on the <varname>console=</varname> kernel
+    for more information on the <varname>console=</varname> kernel parameter.</para>
-    parameter.</para>
 
     <para><filename>systemd-getty-generator</filename> implements
     <citerefentry><refentrytitle>systemd.generator</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para>

man/systemd-machine-id-setup.xml

@@ -55,12 +55,9 @@
       and is different for every booted instance of the
       VM.</para></listitem>
 
-      <listitem><para>Similarly, if run inside a Linux container
+      <listitem><para>Similarly, if run inside a Linux container environment and a UUID is configured for the
-      environment and a UUID is configured for the container, this is
+      container, this is used to initialize the machine ID. For details, see the documentation of the <ulink
-      used to initialize the machine ID. For details, see the
+      url="https://systemd.io/CONTAINER_INTERFACE">Container Interface</ulink>.</para></listitem>
-      documentation of the <ulink
-      url="https://www.freedesktop.org/wiki/Software/systemd/ContainerInterface">Container
-      Interface</ulink>.</para></listitem>
 
       <listitem><para>Otherwise, a new ID is randomly
       generated.</para></listitem>

man/systemd-nspawn.xml

@@ -111,8 +111,7 @@
     container.</para>
 
     <para><command>systemd-nspawn</command> implements the <ulink
-    url="https://www.freedesktop.org/wiki/Software/systemd/ContainerInterface">Container Interface</ulink>
+    url="https://systemd.io/CONTAINER_INTERFACE">Container Interface</ulink> specification.</para>
-    specification.</para>
 
     <para>While running, containers invoked with <command>systemd-nspawn</command> are registered with the
     <citerefentry><refentrytitle>systemd-machined</refentrytitle><manvolnum>8</manvolnum></citerefentry> service that

man/systemd.xml

@@ -280,10 +280,9 @@
     files or parameters passed on the kernel command line. For details, see
     <citerefentry><refentrytitle>systemd.generator</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para>
 
-    <para>Systems which invoke systemd in a container or initrd
+    <para>Systems which invoke systemd in a container or initrd environment should implement the <ulink
-    environment should implement the
+    url="https://systemd.io/CONTAINER_INTERFACE">Container Interface</ulink> or <ulink
-    <ulink url="https://www.freedesktop.org/wiki/Software/systemd/ContainerInterface">Container Interface</ulink> or
+    url="https://www.freedesktop.org/wiki/Software/systemd/InitrdInterface">initrd Interface</ulink>
-    <ulink url="https://www.freedesktop.org/wiki/Software/systemd/InitrdInterface">initrd Interface</ulink>
     specifications, respectively.</para>
   </refsect1>