Bug#950447: Document that persistent journal is now enabled in systemd

[Justin B Rye <justin.byam.rye@gmail.com>]

Andrei POPESCU wrote
> On Mi, 31 mar 21, 17:33:47, Justin B Rye wrote:
>> +<section id="persistent journal">
>> +  <title>Persistent systemd journal</title>
>> +  <para>
>> +    Systemd in bullseye activates its persistent journal functionality
>> +    by default, storing its files in
>> +    <filename>/var/log/journal/</filename>. See <ulink
>> +    url="&url-man;/bullseye/systemd/journald.conf.5.html">journald.conf(5)</ulink>
>> +    for details.
> 
> To me systemd-journald.service(8) seems like a better introduction.

And it does have a fairly conspicuous pointer towards journald.conf(5)
and Storage= in particular.  Fair enough.

> It's probably also worth mentioning that on Debian the journal is 
> readable by members of 'adm', in addition to the default 
> 'systemd-journal' group.

So something like the attached:
-- 
JBR	with qualifications in linguistics, experience as a Debian
	sysadmin, and probably no clue about this particular package

diff --git a/en/whats-new.dbk b/en/whats-new.dbk
index 1e361e61..c271945c 100644
--- a/en/whats-new.dbk
+++ b/en/whats-new.dbk
@@ -182,6 +182,25 @@ linkend="obsolete"/>.
   </para>
 </section>
 
+<section id="persistent journal">
+  <title>Persistent systemd journal</title>
+  <para>
+    Systemd in bullseye activates its persistent journal functionality
+    by default, storing its files in
+    <filename>/var/log/journal/</filename>. See <ulink
+    url="&url-man;/bullseye/systemd/systemd-journald.service.8.html">systemd-journald.service(8)</ulink>
+    for details; note that on Debian the journal is readable for
+    members of <literal>adm</literal>, in addition to the default
+    <literal>systemd-journal</literal> group.
+  </para>
+  <para>
+    This should not interfere with any existing traditional logging
+    daemon such as <systemitem role="package">rsyslog</systemitem>, but
+    users who are not relying on special features of such a daemon may
+    wish to uninstall it and switch over to using only the journal.
+  </para>
+</section>
+
 <section id="major-packages">
   <title>Desktops and well known packages</title>
 <para>