doc: Add some information/recommendation regarding --sysconfdir.

* doc/contributing.texi (Building from Git): Mention sysconfdir along
localstatedir.
* doc/guix.texi (Requirements): Likewise.

2 files changed, 15 insertions, 6 deletions

diff --git a/doc/contributing.texi b/doc/contributing.texi
index 1d7499cfac..7bf350ee0d 100644
--- a/doc/contributing.texi
+++ b/doc/contributing.texi
@@ -135,9 +135,11 @@ Then, run:
 
 @noindent
 ... where @file{/var} is the normal @code{localstatedir} value
-(@pxref{The Store}, for information about this).  Note that you will
-probably not run @command{make install} at the end (you don't have to)
-but it's still important to pass the right @code{localstatedir}.
+(@pxref{The Store}, for information about this) and @file{/etc} is the
+normal @code{sysconfdir} value.  Note that you will probably not run
+@command{make install} at the end (you don't have to) but it's still
+important to pass the right @code{localstatedir} and @code{sysconfdir}
+values, which get recorded in the @code{(guix config)} Guile module.
 
 Finally, you can build Guix and, if you feel so inclined, run the tests
 (@pxref{Running the Test Suite}):
diff --git a/doc/guix.texi b/doc/guix.texi
index e4b664aba9..8fab555e49 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -1016,14 +1016,21 @@ C++11 standard.
 @end itemize
 
 @cindex state directory
+@cindex localstatedir
+@cindex system configuration directory
+@cindex sysconfdir
 When configuring Guix on a system that already has a Guix installation,
 be sure to specify the same state directory as the existing installation
 using the @option{--localstatedir} option of the @command{configure}
 script (@pxref{Directory Variables, @code{localstatedir},, standards,
-GNU Coding Standards}).  Usually, this @var{localstatedir} option is
-set to the value @file{/var}.  The @command{configure} script protects
+GNU Coding Standards}).  Usually, this @var{localstatedir} option is set
+to the value @file{/var}.  The @command{configure} script protects
 against unintended misconfiguration of @var{localstatedir} so you do not
-inadvertently corrupt your store (@pxref{The Store}).
+inadvertently corrupt your store (@pxref{The Store}).  The configuration
+directory should also be configured by setting the @option{--sysconfdir}
+option to the @file{/etc} value, which is the location used by Guix to
+store for example the access control list of authorized machines and the
+definition of offload machines.
 
 @node Running the Test Suite
 @section Running the Test Suite