MISC.: Preparing A Minimal Linux Distro (Odriod C4 Example)


# preparing your linux distro
# before following our tutorials and build your audiophile server

# all info below are applicable to Odroid and others boards
# beware official Odroid Linux Kernel version (v3.16.85) is outdated and do not contains the Native DSD patch
# you need version 4.19.64 or greater to play native DSD,
# however selecting DOP MPD audio output will works with limitation

# To build the MusicLounge Audiophile Server we recommended:
# Armbian Focal Linux Distro on Odroid C4,
# RaspiOS lite (Debian) buster for Raspberry PI 4,
# Debian Standard or Ubuntu server for amd64

# before building you audiophile server the software requirements are simple:
# pi user must be set
# ssh must be set
# alsa must be installed and should recognize your usb dac (command: aplay -l )

# get the img from armbian repository
# burn it on SDCARD (8GB is enough) with any tool like Win32DiskImager app on Windows
# connect your usb DAC to Odroid C4
# boot
# and start the ssh session
# default login/pass root/odroid or root/1234

# the root password needed to be changed immediately
# and a new user (non root) must be created (see below)

New root password: ************************
Repeat password: ************************

Choose default system command shell:

1) bash
2) zsh

Shell: BASH

Creating a new user account. Press  to abort

Please provide a username (eg. your forename): pi
Create password: ************************
Repeat password: ************************

Please provide your real name: Pi

Dear Pi, your account pi has been created and is sudo enabled.
Please use this account for your daily work from now on.

# sanity check

  1. $ sudo apt update -y
  2. $ sudo apt upgrade -y

# on armbian ssh is available by default

# on RaspiOS you need to add an empty file named ssh inside the sdcard before booting the OS

# on Ubuntu server amd64 SSH is activated during installation

# on Debian Standard amd64 you need to install openssh-server pkg

# on Debian netinstall you need to install sudo and pi to sudo group

  1. $ su - root
  2. $ apt install sudo
  3. $ usermod -aG sudo pi

# after the first boot add user pi to sudoers on Debian

  1. $ su - root
  2. $ nano /etc/sudoers

# find line root ALL=(ALL:ALL) ALL and add this line

pi ALL=(ALL:ALL) ALL

# save
# CTRL+X then type y and enter
# go back to user

  1. exit

# install ssh server
# not needed on debian netinstall distro as you normally install SSH server during the installation process

  1. $ sudo apt install openssh-server -y

# active service

  1. $ sudo systemctl start ssh
  2. $ sudo systemctl enable ssh

# HEADLESS PC Server (boot without monitor on)
# BEWARE: if you install a distro supposed to work with GUI like Ubuntu/Debian
# and EVEN IF YOU DID NOT INSTALL A USER INTERFACE you may not be able to boot without a monitor!
# fortunately we can fix it by changed a few lines in grub bootloader to get our headless audio server

# edit grub conf

  1. $ sudo nano /etc/default/grub

# and modify the parameters of GRUB_CMDLINE_LINUX_DEFAULT and GRUB_CMDLINE_LINUX to

GRUB_CMDLINE_LINUX_DEFAULT=""
GRUB_CMDLINE_LINUX="text"

# and obviously uncomment this line

GRUB_TERMINAL=console

# SAVE
# CTRL+X then type y and ENTER key

# now update grub

  1. $ sudo update-grub

that’s it!


# optional: if bash auto-completion (automatically completing of file names, commands and more) is not installed by default

  1. $ sudo apt-get install bash-completion

# audio check
# plug your usb DAC and type the cmd below to list soundcard, your dac must be in the list:

  1. $ aplay -l

# alsa should be already installed (not in ubuntu server no soundcard driver by default)
# if your dac is not visible, install ALSA:

  1. $ sudo apt-get install alsa-utils alsa-tools libasound2

# list devices to see if your DAC is recognized

  1. $ aplay -l
root@odroid:~# aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: ODROIDHDMI [ODROID-HDMI], device 0: I2S dit-hifi-0 []
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 1: D90 [D90], device 0: USB Audio [USB Audio]
  Subdevices: 1/1
  Subdevice #0: subdevice #0

# your usb DAC should be visible in the list

# if still it’s not visible (no soundcard error)
# list installed alsa pkgs, remove them and reinstall alsa
#
# alsa-base pkg could be omited if not present in repository

  1. $ sudo dpkg -l alsa*
  2. $ sudo apt --purge remove alsa-base alsa-firmware-loaders alsa-oss alsa-source alsa-tools alsa-tools-gui alsa-topology-conf alsa-ucm-conf alsamixergui alsa-utils
  3. $ sudo apt-get install alsa-base alsa-utils alsa-tools libasound2
  4. $ sudo reboot

# check alsa status

  1. $ sudo systemctl status alsa-utils.service

# if alsa service is masked unmask it

  1. $ sudo rm /lib/systemd/system/alsa-utils.service
  1. $ sudo systemctl daemon-reload
  1. $ sudo systemctl enable alsa-utils
  2. $ sudo systemctl start alsa-utils

# check the status again everything should be okay

  1. $ sudo systemctl status alsa-utils.service

# on a minimal linux distro with only root you need to create a new user ‘pi’ (or other name) which going to be used to build your MusicLounge audiophile server
# if you’re already login as pi user skip the creation below and go to adding groups directly


# create a user pi:

  1. $ adduser pi
root@odroid:~# adduser pi
Adding user `pi' ...
Adding new group `pi' (1000) ...
Adding new user `pi' (1000) with group `pi' ...
Creating home directory `/home/pi' ...
Copying files from `/etc/skel' ...
Enter new UNIX password:
Retype new UNIX password:
passwd: password updated successfully
Changing the user information for pi
Enter the new value, or press ENTER for the default
        Full Name []: PI
        Room Number []:
        Work Phone []:
        Home Phone []:
        Other []:
Is the information correct? [Y/n] y

# add new user to all default groups

  1. $ sudo usermod -aG adm,dialout,cdrom,sudo,audio,www-data,video,plugdev,games,users,input,netdev pi
  1. $ groups pi

# reboot, login pi (skip this step if you are already logged in as pi user)

  1. $ sudo reboot
login as: pi
pi@192.168.1.11's password:
  ___      _           _     _    ____ _  _
 / _ \  __| |_ __ ___ (_) __| |  / ___| || |
| | | |/ _` | '__/ _ \| |/ _` | | |   | || |_
| |_| | (_| | | | (_) | | (_| | | |___|__   _|
 \___/ \__,_|_|  \___/|_|\__,_|  \____|  |_|

Welcome to Armbian 21.05.2 Focal with Linux 5.10.34-meson64

System load:   45%              Up time:       0 min
Memory usage:  4% of 3.73G      IP:            192.168.1.11
CPU temp:      42°C             Usage of /:    10% of 14G
RX today:      31.0 MiB

[ 0 security updates available, 4 updates total: apt upgrade ]

To run a command as administrator (user "root"), use "sudo ".
See "man sudo_root" for details.

pi@odroidc4:~$

# your linux distro is now ready

# click the link below to follow our tutorials and build the MusicLounge Audiophile Server

BUILD THE MUSICLOUNGE AUDIOPHILE DISTRO