doc: Simplify installation instructions

* doc/guix.texi (Installation):
- Move the definition of "foreign distro" out of quotation
- Repeat overwrite warning
- Remove superfluous commentary

* doc/guix.texi (Binary Installation):
- Clarify that installing on a foreign distro has two methods: using
  packaged binaries and building from source
- Add cross reference to "Building from Git"
- Move the foreign distro installation instructions out of quotation
- Move directions for 'guix-install.sh' after instructions to use
  distribution-specific package managers
- Specify "distributions" as "GNU/Linux distributions"
- Add GnuPG as a requirement for 'guix-install.sh'
- Add comma after "Likewise"
- Remove redundant instructions to use 'guix-install.sh'
- Split the requirements between system requirements for binary
  installations, GNU/Linux or GNU/Hurd, and requirements for running
  'guix-install.sh'
- Clarify that 'guix-install.sh' guides users through the steps
- Summarize the steps 'guix-install.sh' follows rather than try to
  detail them
- Make explicit that the 'guix-install.sh' default is to download
  substitutes
- Emphasize that the substitute authorization code is an example and
  may need modification

Link: <https://lists.gnu.org/archive/html/guix-devel/2024-03/msg00023.html>
Signed-off-by: Maxim Cournoyer <maxim.cournoyer@gmail.com>

1 files changed, 51 insertions, 245 deletions

diff --git a/doc/guix.texi b/doc/guix.texi
index acfe60b47a..3cae7495f6 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -691,19 +691,20 @@ to join!  @xref{Contributing}, for information about how you can help.
 @chapter Installation
 
 @cindex installing Guix
+@cindex foreign distro
+@cindex Guix System
+You can install the package management tool Guix on top of an existing
+GNU/Linux or GNU/Hurd system@footnote{Hurd support is currently
+limited.}, referred to as a @dfn{foreign distro}.  If, instead, you want
+to install the complete, standalone GNU system distribution,
+@dfn{Guix@tie{}System}, @pxref{System Installation}.  This section is
+concerned only with the installation of Guix on a foreign distro.
 
-@quotation Note
-We recommend the use of this
-@uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
-shell installer script} to install Guix on top of a running GNU/Linux system,
-thereafter called a @dfn{foreign distro}@footnote{This section is concerned
-with the installation of the package manager, which can be done on top of a
-running GNU/Linux system.  If, instead, you want to install the complete GNU
-operating system, @pxref{System Installation}.}.  @xref{Binary
-Installation}, for more information.
+@quotation Important
+This section only applies to systems without Guix.  Following it for
+existing Guix installations will overwrite important system files.
 @end quotation
 
-@cindex foreign distro
 @cindex directories related to foreign distro
 When installed on a foreign distro, GNU@tie{}Guix complements the available
 tools without interference.  Its data lives exclusively in two directories,
@@ -713,11 +714,6 @@ such as @file{/etc}, are left untouched.
 Once installed, Guix can be updated by running @command{guix pull}
 (@pxref{Invoking guix pull}).
 
-If you prefer to perform the installation steps manually or want to tweak
-them, you may find the following subsections useful.  They describe the
-software requirements of Guix, as well as how to install it manually and get
-ready to use it.
-
 @menu
 * Binary Installation::         Getting Guix running in no time!
 * Requirements::                Software needed to build and run Guix.
@@ -735,226 +731,69 @@ ready to use it.
 @cindex installer script
 This section describes how to install Guix from a self-contained tarball
 providing binaries for Guix and for all its dependencies.  This is often
-quicker than installing from source, which is described in the next
-sections.  Binary installation requires a system using a Hurd or Linux
-kernel; the GNU@tie{}tar and Xz commands must also be available.
+quicker than installing from source, described later (@pxref{Building
+from Git}).
 
 @quotation Important
 This section only applies to systems without Guix.  Following it for
 existing Guix installations will overwrite important system files.
+@end quotation
 
-@c Note duplicated from the ``Installation'' node.
-We recommend the use of this
-@uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
-shell installer script}.  The script automates the download, installation, and
-initial configuration steps described below.  It should be run as the root
-user.  As root, you can thus run this:
-
-@example
-cd /tmp
-wget https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh
-chmod +x guix-install.sh
-./guix-install.sh
-@end example
-
-The script automates the download, installation, and initial
-configuration of Guix, interactively offering various configuration
-options.
-
-@cindex uninstalling Guix
-@cindex uninstallation, of Guix
-Should you eventually want to uninstall Guix, run the same script with
-the @option{--uninstall} flag:
-
-@example
-./guix-install.sh --uninstall
-@end example
-
-With @option{--uninstall}, the script irreversibly deletes all the Guix
-files, configuration, and services.
+Some GNU/Linux distributions, such as Debian, Ubuntu, and openSUSE
+provide Guix through their own package managers.  The version of Guix
+may be older than @value{VERSION} but you can update it afterwards by
+running @samp{guix pull}.
 
-If you're running Debian or a derivative such as Ubuntu, you can instead
-install the package (it might be a version older than @value{VERSION}
-but you can update it afterwards by running @samp{guix pull}):
+For Debian and Ubuntu-based systems, call:
 
 @example
 sudo apt install guix
 @end example
 
-Likewise on openSUSE:
+Likewise, on openSUSE:
 
 @example
 sudo zypper install guix
 @end example
 
-When you're done, @pxref{Application Setup} for extra configuration you
-might need, and @ref{Getting Started} for your first steps!
-@end quotation
-
-Installing goes along these lines:
-
-@enumerate
-@item
-@cindex downloading Guix binary
-Download the binary tarball from
-@indicateurl{@value{BASE-URL}/guix-binary-@value{VERSION}.x86_64-linux.tar.xz},
-where @code{x86_64-linux} can be replaced with @code{i686-linux} for an
-@code{i686} (32-bits) machine already running the kernel Linux, and so on
-(@pxref{GNU Distribution}).
-
-@c The following is somewhat duplicated in ``System Installation''.
-Make sure to download the associated @file{.sig} file and to verify the
-authenticity of the tarball against it, along these lines:
-
-@example
-$ wget @value{BASE-URL}/guix-binary-@value{VERSION}.x86_64-linux.tar.xz.sig
-$ gpg --verify guix-binary-@value{VERSION}.x86_64-linux.tar.xz.sig
-@end example
-
-If that command fails because you do not have the required public key,
-then run this command to import it:
-
-@example
-$ wget '@value{OPENPGP-SIGNING-KEY-URL}' \
-      -qO - | gpg --import -
-@end example
+The Guix project also provides a shell script, @file{guix-install.sh},
+which automates the binary installation process without use of a foreign
+distro package
+manager@footnote{@uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh}}.
+Use of @file{guix-install.sh} requires Bash, GnuPG, GNU@tie{}tar, wget,
+and Xz.
 
-@noindent
-and rerun the @code{gpg --verify} command.
+The script guides you through the following:
 
-Take note that a warning like ``This key is not certified with a trusted
-signature!'' is normal.
+@itemize
+@item Downloading and extracting the binary tarball
+@item Setting up the build daemon
+@item Making the ‘guix’ command available to non-root users
+@item Configuring substitute servers
+@end itemize
 
-@c end authentication part
-
-@item
-Now, you need to become the @code{root} user.  Depending on your distribution,
-you may have to run @code{su -} or @code{sudo -i}.  As @code{root}, run:
+As root, run:
 
 @example
 # cd /tmp
-# tar --warning=no-timestamp -xf \
-     /path/to/guix-binary-@value{VERSION}.x86_64-linux.tar.xz
-# mv var/guix /var/ && mv gnu /
-@end example
-
-This creates @file{/gnu/store} (@pxref{The Store}) and @file{/var/guix}.
-The latter contains a ready-to-use profile for @code{root} (see next
-step).
-
-Do @emph{not} unpack the tarball on a working Guix system since that
-would overwrite its own essential files.
-
-The @option{--warning=no-timestamp} option makes sure GNU@tie{}tar does
-not emit warnings about ``implausibly old time stamps'' (such
-warnings were triggered by GNU@tie{}tar 1.26 and older; recent
-versions are fine).
-They stem from the fact that all the
-files in the archive have their modification time set to 1 (which
-means January 1st, 1970).  This is done on purpose to make sure the
-archive content is independent of its creation time, thus making it
-reproducible.
-
-@item
-Make the profile available under @file{~root/.config/guix/current}, which is
-where @command{guix pull} will install updates (@pxref{Invoking guix pull}):
-
-@example
-# mkdir -p ~root/.config/guix
-# ln -sf /var/guix/profiles/per-user/root/current-guix \
-         ~root/.config/guix/current
-@end example
-
-Source @file{etc/profile} to augment @env{PATH} and other relevant
-environment variables:
-
-@example
-# GUIX_PROFILE="`echo ~root`/.config/guix/current" ; \
-  source $GUIX_PROFILE/etc/profile
+# wget https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh
+# chmod +x guix-install.sh
+# ./guix-install.sh
 @end example
 
-@item
-Create the group and user accounts for build users as explained below
-(@pxref{Build Environment Setup}).
-
-@item
-Run the daemon, and set it to automatically start on boot.
-
-If your host distro uses the systemd init system, this can be achieved
-with these commands:
-
-@c Versions of systemd that supported symlinked service files are not
-@c yet widely deployed, so we should suggest that users copy the service
-@c files into place.
-@c
-@c See this thread for more information:
-@c https://lists.gnu.org/archive/html/guix-devel/2017-01/msg01199.html
-
-@example
-# cp ~root/.config/guix/current/lib/systemd/system/gnu-store.mount \
-     ~root/.config/guix/current/lib/systemd/system/guix-daemon.service \
-     /etc/systemd/system/
-# systemctl enable --now gnu-store.mount guix-daemon
-@end example
-
-You may also want to arrange for @command{guix gc} to run periodically:
-
-@example
-# cp ~root/.config/guix/current/lib/systemd/system/guix-gc.service \
-     ~root/.config/guix/current/lib/systemd/system/guix-gc.timer \
-     /etc/systemd/system/
-# systemctl enable --now guix-gc.timer
-@end example
-
-You may want to edit @file{guix-gc.service} to adjust the command line
-options to fit your needs (@pxref{Invoking guix gc}).
-
-If your host distro uses the Upstart init system:
-
-@example
-# initctl reload-configuration
-# cp ~root/.config/guix/current/lib/upstart/system/guix-daemon.conf \
-     /etc/init/
-# start guix-daemon
-@end example
-
-Otherwise, you can still start the daemon manually with:
-
-@example
-# ~root/.config/guix/current/bin/guix-daemon \
-       --build-users-group=guixbuild
-@end example
-
-@item
-Make the @command{guix} command available to other users on the machine,
-for instance with:
-
-@example
-# mkdir -p /usr/local/bin
-# cd /usr/local/bin
-# ln -s /var/guix/profiles/per-user/root/current-guix/bin/guix
-@end example
-
-It is also a good idea to make the Info version of this manual available
-there:
-
-@example
-# mkdir -p /usr/local/share/info
-# cd /usr/local/share/info
-# for i in /var/guix/profiles/per-user/root/current-guix/share/info/* ;
-  do ln -s $i ; done
-@end example
-
-That way, assuming @file{/usr/local/share/info} is in the search path,
-running @command{info guix} will open this manual (@pxref{Other Info
-Directories,,, texinfo, GNU Texinfo}, for more details on changing the
-Info search path).
+@quotation Note
+By default, @file{guix-install.sh} will configure Guix to download
+pre-built package binaries, called @dfn{substitutes}
+(@pxref{Substitutes}), from the project's build farms.  If you choose
+not to permit this, Guix will build @emph{everything} from source,
+making each installation and upgrade very expensive.  @xref{On Trusting
+Binaries} for a discussion of why you may want to build packages from
+source.
 
-@item
 @cindex substitutes, authorization thereof
 To use substitutes from @code{@value{SUBSTITUTE-SERVER-1}},
-@code{@value{SUBSTITUTE-SERVER-2}} or a mirror (@pxref{Substitutes}),
-authorize them:
+@code{@value{SUBSTITUTE-SERVER-2}} or a mirror, you must authorize them.
+For example,
 
 @example
 # guix archive --authorize < \
@@ -962,45 +801,8 @@ authorize them:
 # guix archive --authorize < \
      ~root/.config/guix/current/share/guix/@value{SUBSTITUTE-SERVER-2}.pub
 @end example
-
-@quotation Note
-If you do not enable substitutes, Guix will end up building
-@emph{everything} from source on your machine, making each installation
-and upgrade very expensive.  @xref{On Trusting Binaries}, for a
-discussion of reasons why one might want do disable substitutes.
 @end quotation
 
-@item
-Each user may need to perform a few additional steps to make their Guix
-environment ready for use, @pxref{Application Setup}.
-@end enumerate
-
-Voilà, the installation is complete!
-
-You can confirm that Guix is working by installing a sample package into
-the root profile:
-
-@example
-# guix install hello
-@end example
-
-The binary installation tarball can be (re)produced and verified simply
-by running the following command in the Guix source tree:
-
-@example
-make guix-binary.@var{system}.tar.xz
-@end example
-
-@noindent
-...@: which, in turn, runs:
-
-@example
-guix pack -s @var{system} --localstatedir \
-  --profile-name=current-guix guix
-@end example
-
-@xref{Invoking guix pack}, for more info on this handy tool.
-
 @node Requirements
 @section Requirements
 
@@ -1194,6 +996,9 @@ Some of them require a lot of storage space to hold VM images.
 
 Again in case of test failures, please send @email{bug-guix@@gnu.org}
 all the details.
+When you're done installing Guix, @pxref{Application Setup} for extra
+configuration you might need, and @ref{Getting Started} for your first
+steps!
 
 @node Setting Up the Daemon
 @section Setting Up the Daemon
@@ -17726,6 +17531,7 @@ configuration (@pxref{Using the Configuration System}).
 
 @table @asis
 @item @code{kernel} (default: @code{linux-libre})
+@c footnote duplicated in @pxref{Installation}
 The package object of the operating system kernel to
 use@footnote{Currently only the Linux-libre kernel is fully supported.
 Using GNU@tie{}mach with the GNU@tie{}Hurd is experimental and only