perlsynology

PERLSYNOLOGY(1)        Perl Programmers Reference Guide        PERLSYNOLOGY(1)

NAME
       perlsynology - Perl 5 on Synology DSM systems

DESCRIPTION
       Synology manufactures a vast number of Network Attached Storage (NAS)
       devices that are very popular in large organisations as well as small
       businesses and homes.

       The NAS systems are equipped with Synology Disk Storage Manager (DSM),
       which is a trimmed-down Linux system enhanced with several tools for
       managing the NAS. There are several flavours of hardware: Marvell
       Armada (ARMv5tel, ARMv7l), Intel Atom (i686, x86_64), Freescale QorIQ
       (PPC), and more. For a full list see the Synology FAQ
       <http://forum.synology.com/wiki/index.php/What_kind_of_CPU_does_my_NAS_have>.

       Since it is based on Linux, the NAS can run many popular Linux software
       packages, including Perl. In fact, Synology provides a ready-to-install
       package for Perl, depending on the version of DSM the installed perl
       ranges from 5.8.6 on DSM-4.3 to 5.24.0 on DSM-6.1.

       There is an active user community that provides many software packages
       for the Synology DSM systems; at the time of writing this document they
       provide Perl version 5.24.1.

       This document describes various features of Synology DSM operating
       system that will affect how Perl 5 (hereafter just Perl) is configured,
       compiled and/or runs. It has been compiled and verified by Johan
       Vromans for the Synology DS413 (QorIQ), with feedback from H.Merijn
       Brand (DS213, ARMv5tel and RS815, Intel Atom x64).

   Setting up the build environment
       DSM 5

       As DSM is a trimmed-down Linux system, it lacks many of the tools and
       libraries commonly found on Linux. The basic tools like sh, cp, rm,
       etc. are implemented using BusyBox
       <http://en.wikipedia.org/wiki/BusyBox>.

       o   Using your favourite browser open the DSM management page and start
           the Package Center.

       o   If you want to smoke test Perl, install "Perl".

       o   In Settings, add the following Package Sources:

             http://www.cphub.net
             http://packages.quadrat4.de

       o   Still in Settings, in Channel Update, select Beta Channel.

       o   Press Refresh. In the left panel the item "Community" will appear.
           Click it. Select "Bootstrap Installer Beta" and install it.

       o   Likewise, install "iPKGui Beta".

           The application window should now show an icon for iPKGui.

       o   Start iPKGui. Install the packages "make", "gcc" and "coreutils".

           If you want to smoke test Perl, install "patch".

       The next step is to add some symlinks to system libraries. For example,
       the development software expect a library "libm.so" that normally is a
       symlink to "libm.so.6". Synology only provides the latter and not the
       symlink.

       Here the actual architecture of the Synology system matters. You have
       to find out where the gcc libraries have been installed. Look in /opt
       for a directory similar to arm-none-linux-gnueab or powerpc-linux-
       gnuspe. In the instructions below I'll use powerpc-linux-gnuspe as an
       example.

       o   On the DSM management page start the Control Panel.

       o   Click Terminal, and enable SSH service.

       o   Close Terminal and the Control Panel.

       o   Open a shell on the Synology using ssh and become root.

       o   Execute the following commands:

             cd /lib
             ln -s libm.so.6 libm.so
             ln -s libcrypt.so.1 libcrypt.so
             ln -s libdl.so.2 libdl.so
             cd /opt/powerpc-linux-gnuspe/lib  (or
                                               /opt/arm-none-linux-gnueabi/lib)
             ln -s /lib/libdl.so.2 libdl.so

       WARNING: When you perform a system software upgrade, these links will
       disappear and need to be re-established.

       DSM 6

       Using iPkg has been deprecated on DSM 6, but an alternative is
       available for DSM 6: entware/opkg. For instructions on how to use that,
       please read Install Entware-ng on Synology NAS
       <https://github.com/Entware-ng/Entware-ng/wiki/Install-on-Synology-NAS>

       That sadly does not (yet) work on QorIQ. At the moment of writing, the
       supported architectures are armv5, armv7, mipsel, wl500g, x86_32, and
       x86_64.  Check here <http://pkg.entware.net/binaries/> for supported
       platforms.

       Entware-ng comes with a precompiled 5.24.1 (June 2017) that allowes
       building shared XS code. Note that this installation does not use a
       site_perl folder. The available "cpan" works. If all required
       development packages are installed too, also for XS.

   Compiling Perl 5
       When the build environment has been set up, building and testing Perl
       is straightforward. The only thing you need to do is download the
       sources as usual, and add a file Policy.sh as follows:

         # Administrivia.
         perladmin="your.email@goes.here"

         # Install Perl in a tree in /opt/perl instead of /opt/bin.
         prefix=/opt/perl

         # Select the compiler. Note that there is no 'cc' alias or link.
         cc=gcc

         # Build flags.
         ccflags="-DDEBUGGING"

         # Library and include paths.
         libpth="/lib"
         locincpth="/opt/include"
         loclibpth="/lib"

       You may want to create the destination directory and give it the right
       permissions before installing, thus eliminating the need to build Perl
       as a super user.

       In the directory where you unpacked the sources, issue the familiar
       commands:

         ./Configure -des
         make
         make test
         make install

   Known problems
       Configure

       No known problems yet

       Build

       Error message "No error definitions found".
           This error is generated when it is not possible to find the local
           definitions for error codes, due to the uncommon structure of the
           Synology file system.

           This error was fixed in the Perl development git for version 5.19,
           commit 7a8f1212e5482613c8a5b0402528e3105b26ff24.

       Failing tests

       ext/DynaLoader/t/DynaLoader.t
           One subtest fails due to the uncommon structure of the Synology
           file system. The file /lib/glibc.so is missing.

           WARNING: Do not symlink /lib/glibc.so.6 to /lib/glibc.so or some
           system components will start to fail.

   Smoke testing Perl 5
       If building completes successfully, you can set up smoke testing as
       described in the Test::Smoke documentation.

       For smoke testing you need a running Perl. You can either install the
       Synology supplied package for Perl 5.8.6, or build and install your
       own, much more recent version.

       Note that I could not run successful smokes when initiated by the
       Synology Task Scheduler. I resorted to initiating the smokes via a cron
       job run on another system, using ssh:

         ssh nas1 wrk/Test-Smoke/smoke/smokecurrent.sh

       Local patches

       When local patches are applied with smoke testing, the test driver will
       automatically request regeneration of certain tables after the patches
       are applied. The Synology supplied Perl 5.8.6 (at least on the DS413)
       is NOT capable of generating these tables. It will generate opcodes
       with bogus values, causing the build to fail.

       You can prevent regeneration by adding the setting

         'flags' => 0,

       to the smoke config, or by adding another patch that inserts

         exit 0 if $] == 5.008006;

       in the beginning of the "regen.pl" program.

   Adding libraries
       The above procedure describes a basic environment and hence results in
       a basic Perl. If you want to add additional libraries to Perl, you may
       need some extra settings.

       For example, the basic Perl does not have any of the DB libraries (db,
       dbm, ndbm, gdsm). You can add these using iPKGui, however, you need to
       set environment variable LD_LIBRARY_PATH to the appropriate value:

         LD_LIBRARY_PATH=/lib:/opt/lib
         export LD_LIBRARY_PATH

       This setting needs to be in effect while Perl is built, but also when
       the programs are run.

REVISION
       June 2017, for Synology DSM 5.1.5022 and DSM 6.1-15101-4.

AUTHOR
       Johan Vromans <jvromans@squirrel.nl> H. Merijn Brand
       <h.m.brand@xs4all.nl>

perl v5.30.0                      2023-11-23                   PERLSYNOLOGY(1)