documentation: add description for watchdog device path

Document the command line parameter and the system configuration file
setting.

1 files changed, 13 insertions, 2 deletions

diff --git a/man/systemd-system.conf.xml b/man/systemd-system.conf.xml
index 43715813ed..08f6c91901 100644
--- a/man/systemd-system.conf.xml
+++ b/man/systemd-system.conf.xml
@@ -161,8 +161,10 @@
         <literal>d</literal>, <literal>w</literal>). If
         <varname>RuntimeWatchdogSec=</varname> is set to a non-zero
         value, the watchdog hardware
-        (<filename>/dev/watchdog</filename>) will be programmed to
-        automatically reboot the system if it is not contacted within
+        (<filename>/dev/watchdog</filename> or the path specified with
+        <varname>WatchdogDevice=</varname> or the kernel option
+        <varname>systemd.watchdog-device=</varname>) will be programmed
+        to automatically reboot the system if it is not contacted within
         the specified timeout interval. The system manager will ensure
         to contact it at least once in half the specified timeout
         interval. This feature requires a hardware watchdog device to
@@ -180,6 +182,15 @@
       </varlistentry>
 
       <varlistentry>
+        <term><varname>WatchdogDevice=</varname></term>
+
+        <listitem><para>Configure the hardware watchdog device that the
+        runtime and shutdown watchdog timers will open and use. Defaults
+        to <filename>/dev/watchdog</filename>. This setting has no
+        effect if a hardware watchdog is not available.</para></listitem>
+      </varlistentry>
+
+      <varlistentry>
         <term><varname>CapabilityBoundingSet=</varname></term>
 
         <listitem><para>Controls which capabilities to include in the