Before you start

• At the moment this only works on DSM versions that are listed in this file
• A possible alternative to synouidmod is editing /etc/passwd and /etc/group manually and use synouser --rebuild all to synchronize

Build synouidmod

This script uses Docker to build the synouidmod binary for your Synology DSM version and platform.

Depending on your hardware, it may take a while to complete. After the message "Available platforms" it may seem like the system hangs but it is not.

You can also check here if a binary is already available. If so, you can use it and you don't have to compile it yourself.

For more information about the Synology Build Environment see the Synology Developer Guide.

Findings for synouidmod ⚠️

• Before you start, read the README of synouidmod
• Backup /var/run/synosdk before using synouidmod
• Changing a user with a UID less than or equal to 1024 is not recommended
• Using a UID less than or equal to 1024 is not recommended
• Binaries built for the x86 architecture (e.g. Intel and AMD processors) can probably be used interchangeably.

How to use

Git clone this repository.

git clone https://github.com/technorabilia/build-synouidmod.git

Check your DSM version and platform.

$ uname -a
Linux DS716 3.10.105 #25556 SMP Thu Mar 4 18:00:29 CST 2021 x86_64 GNU/Linux synology_braswell_716+
$ grep productversion /etc.defaults/VERSION
productversion="6.2.4"
$

In this case the version number is 6.2 and the platform is braswell.

Change the VERSION and PLATFORM in build.sh appropriately.

VERSION=6.2
PLATFORM=braswell

Execute the build script.

. ./build.sh

After completion the synouidmod binary will be in the directory ./output.

You can copy this file to the directory /usr/local/sbin on your Synology.

Access the build environment

After the build, you can access the build environment with the following docker run command.

$ docker run -it --rm --name synobuild synobuild
root@397b92bfbecd:/toolkit/build_env/ds.braswell-6.2# ls
PkgVersion  boot  etc   lib    mnt  pkgscripts  root  sbin    srv  tmp  var
bin         dev   home  lib64  opt  proc        run   source  sys  usr
root@397b92bfbecd:/toolkit/build_env/ds.braswell-6.2# exit
exit
$

Cleanup

Because the image can be quite large, you can also delete it if you no longer need it.

$ docker image ls synobuild
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
synobuild           latest              2568d28931d8        2 hours ago         7.93GB
$ docker image rm synobuild
Untagged: synobuild:latest
Deleted: sha256:2568d28931d86d6d4c23506b9bf0dba54ef62ca833197df7fa96b77443fe4bb8
$

Remarks

During the build the available platforms for the selected DSM version are listed.

At the time of writing the available platforms for DSM 6.2 are:

• 6281
• alpine
• alpine4k
• apollolake
• armada370
• armada375
• armada37xx
• armada38x
• armadaxp
• avoton
• braswell
• broadwell
• broadwellnk
• bromolow
• cedarview
• comcerto2k
• denverton
• dockerx64
• evansport
• geminilake
• grantley
• hi3535
• kvmx64
• monaco
• purley
• qoriq
• rtd1296
• v1000
• x64

Acknowledgements

All credit goes to sunnyone for writing this handy utility.