I use a Raspberry PI4 to provide NFSv4 and Samba shares. An external 3TB hard disk is connected to the USB3 port of the PI4 as /MDrive. This disk has the following important directories at the root
- Music - This has all the music files
- data - This stores all data for mpdev. mpdev is used for storing the play counts, ratings, karma (a value indicating how much a particular song is liked by you).
- playlists - This stores all playlists
- cache - The mpd config uses this directory for storing the mpd database information
This scheme allows me to share my Music Directory to all clients. They all mount /MDrive of PI4 at /var/lib/mpd/MDrive to access the data and Music directories on the drive. These clients are mostly Single Board Computers (SBCs), mix of Raspbery PIs, Banana PIs, Allo sparky SBC. All of these mount the filesystem using automount. Music playback on clients is done via Music Player Daemon. These SBCs have been installed in each of my room (Living Room, Music Room, two bedrooms and one device which is connected to a Headphone amp. The power supply of these boards are connected to WiFI switches which can be remotely turned off. The PI4 also runs mpd, but the configuration provides proxy database service for all clients. When you add music, it needs to be added to external hard disk mounted on PI4. mpd automatically updates it's database. Nothing needs to be done on the clients. They all get the updated database instantly.
# mpd.conf database configuration entry for PI4
music_directory "/MDrive/Music"
playlist_directory "/MDrive/playlists"
database {
plugin "simple"
path "/MDrive/data/tag_cache.PI4"
cache_directory "/MDrive/cache"
}
# mpd.conf database configuration entry for client
music_directory "/var/lib/mpd/MDrive/Music"
playlist_directory "/var/lib/mpd/MDrive/playlists"
database {
plugin "proxy"
host "MusicPI"
port "6600"
}
The MusicPI above refers to host in /etc/hosts or the IP address the PI4 server. For me it is
192.168.2.101 MusicPI
The problem pistop solves is a synchronized mounting of the shared Music Directory, starting of mpd and automount service as soon as the PI4 server is powered on and up. This is achieved by having a service known as fclient on the clients and a service known as fserver on the NFSv4 server (PI4). These services use supervise, tcpclient, tcpserver from the ucspi-tcp package. I use the fclient service on my laptop too. It automatically starts the mpd daemon, the moment it sees the NFSv4 server (PI4) up running the fserver service. In case, I'm done with listening to Music, I shutdown the PI4 server. The fclient service detects that and stops the automount service, unmounts the NFS share and stops the mpd daemon. This prevents programs like ls from hanging when doing a listing of your home directory.
There are two other features of pistop.
- Backing up configuration and important files. You need to create environment variables BACKUP and DEST in /service/fclient/variables or /service/fserver/variables directory. The fserver runs on your file server while the fclient runs on the client devices.
- Automatic update of your device. You need to have packages that need automatic updation in the environment variable UPGRADE in /service/update/variables directory. The at(1) command is used to update packages. You can have any package listed in the file /service/update/variables/UPGRADE.
So when I retire for the night to get a good night sleep, I use an android app known as ssh button to shutdown the NFSv4 server. The moment the server shuts down, all my clients shutdown together. The PI4 has a design problem. It doesn't shut off the power to the USB3 ports when shutdown. Due to his, any hard disk connected to PI4 will not spin down when the PI4 is shutdown. I use uhubctl to shutdown power to the usb port. uhubctl is utility to control USB power per-port on smart USB hubs. I have also created a systemd service /lib/systemd/system/usb3-poweroff.service to use uhubctl to turn off power.
[Unit]
Description=Turns off usb3 power on shutdown/reboot
DefaultDependencies=no
After=umount.target
[Service]
Type=oneshot
ExecStart=/usr/sbin/uhubctl -a 0 -l 2
[Install]
WantedBy=halt.target poweroff.target
The above will work if your drive is unmounted. To achieve unmounting of drives, I call my own shutdown script (pishutdown).
/home/pi/bin/pishutdown
#!/bin/sh
if [ $# -gt 1 ] ; then
if [ " $1" = " -h" ] ; then
# shut down mpdev service
/usr/bin/svc -d /service/fserver /service/mpdev
sync
systemctl stop svscan mpd smbd nmbd nfs-server
umount /home/pi/MDrive
sync
fi
fi
exec /sbin/shutdown $*
Using home automation, I then switch off the power output to each and very adaptor thereby saving around 0.05 kwhr of electricity per device every day. The PI4 consumes around 2 units per month if you leave them switched on 24x7. You could say that these SBC consume miniscule power, but this kind of philosophy has led us mankind to plunder this planet. Global Warming is a stark reality of the day and we should try to conserve electricity as much as possible. Please note that if you use wifi switches to switch off devices, these switches by itself will consume 1.5-2 watts even when off, resulting in around 1.5 Units of electricity every month.
You can take a look at the files, configuration for my server and client in the directory example_config. Along with pistop, I use mdev to maintain playcounts and ratings. This is something that mpd(1) doesn't provide out of the box.
On the server (use the IP Address of your own server). This will create fserver supervise service in /service
# apt-get update
# apt-get install pistop
# /usr/libexec/pistop/create_service --servicedir=/service --service_name=fserver --user=pi --host=192.168.1.101 --port=5555 --add-service
On each client (use IP Address of your server). This will create fclient supervise service in /service
# apt-get update
# apt-get install pistop
# /usr/libexec/pistop/create_service --servicedir=/service --service_name=fclient --user=pi --host=192.168.1.101 --port=5555 --add-service
If you want to have your clients shutdown itself when the server is powered off, create POWER_OFF enviroment variable by doing this
sudo sh -c "echo 1 > /service/fclient/variables/POWER_OFF"
Client AUTOMOUNT SETUP
file /etc/auto.master.d/mpd.autofs
/var/lib/mpd /etc/autofs.mounts timeout=60
file /etc/autofs.mounts
MDrive -fstype=nfs,vers=4,soft,timeo=5,retry=1 MusicPI:/MDrive
Server NFSv4 SETUP
file /etc/exports
/MDrive 192.168.2.0/24(rw,async,no_root_squash,subtree_check,anonuid=1000,anongid=1000)
file /etc/fstab
proc /proc proc defaults 0 0
PARTUUID=5e3da3da-01 /boot vfat defaults 0 2
PARTUUID=5e3da3da-02 / ext4 defaults,noatime 0 1
UUID=20bcc800-9dce-4734-947d-6d760b36a4de /MDrive ext4 defaults,noatime,noauto,x-systemd.automount 0 2
tmpfs /tmp tmpfs defaults,size=250M,noatime,nodev,nosuid,mode=1777 0 0
tmpfs /var/tmp tmpfs defaults,size=200M,noatime,nodev,nosuid,mode=1777 0 0
# a swapfile is not a swap partition, no line here
# use dphys-swapfile swap[on|off] for that
NOTE: You only need to add the line having UUID= in your /etc/fstab. Your UUID for your external drive will be different. Use blkid(1) to find that out.
Server Samba SETUP
[global]
workgroup = WORKGROUP
mangled names = no
fruit:encoding = native
unix charset = UTF-8
catia:mappings = 0x22:0xa8,0x2a:0xa4,0x2f:0xf8,0x3a:0xf7,0x3c:0xab,0x3e:0xbb,0x3f:0xbf,0x5c:0xff,0x7c:0xa6
[NAS]
comment = Music Folder Share
path = /home/pi/MDrive/Music
browseable = yes
create mask = 0755
directory mask = 0755
valid users = pi, root
admin users = pi
writeable = yes
vfs objects = catia
; locking = no
; oplocks = no
; kernel oplocks = no
; posix locking = no
max connections = 8
Update Service
You can have your SBC automatically updated. You can have list of packages that the service will automatically update by creating the environment variable UPGRADE. The default value for this environment variable is ucspi-tcp mpdev libqmail indimail-mini daemontools pistop mpd. You can edit the file /service/update/variables/UPGRADE to update the environment variable.
$ sudo /usr/libexec/pistop/create_service --service_name=update --user=pi --add-service
RSYNC Service
You can have a rsync service running on your SBC. rsync service is useful if you want to transfer music files from any computer to the SBC. This can be created by running
$ sudo /usr/libexec/pistop/create_service --service_name=rsync --add-service
Prebuilt binaries using openSUSE Build Service are available for pistop for
- Debian (including ARM images for Debian 10 which work (and tested) for RaspberryPI (model 2,3 & 4) and Allo Sparky)
- openSUSE Tumbleweed
- Ubuntu
- Arch Linux
- Fedora
Use the below url for installation
https://software.opensuse.org//download.html?project=home%3Ambhangui%3Araspi&package=pistop
debian/ubuntu repositories already has daemontools and ucspi-tcp which are far behind in terms of feature list that the indimail-mta repo provides. When you install pistop, apt-get may pull the wrong version with limited features. Also apt-get install mpdev will get installed with errors, leading to an incomplete setup. You need to ensure that the two packages get installed from the indimail-mta repository instead of the debian repository. If you don't do this, pistop will not function correctly as it depends on setting of proper global envirnoment variables. Global environment variabels are not supported by daemontools from the official debian repository. Additionally, the official ucspi-tcp package from the debian repository doesn't support TLS, which will result in services that depend on TLS not functioning.
All you need to do is set a higher preference for the indimail-mta repository by creating /etc/apt/preferences.d/preferences with the following contents
$ sudo /bin/bash
# cat > /etc/apt/preferences.d/preferences <<EOF
Package: *
Pin: origin download.opensuse.org
Pin-Priority: 1001
EOF
You can verify this by doing
$ apt policy daemontools ucspi-tcp
daemontools:
Installed: 2.11-1.1+1.1
Candidate: 2.11-1.1+1.1
Version table:
1:0.76-7 500
500 http://raspbian.raspberrypi.org/raspbian buster/main armhf Packages
*** 2.11-1.1+1.1 1001
1001 http://download.opensuse.org/repositories/home:/indimail/Debian_10 Packages
100 /var/lib/dpkg/status
ucspi-tcp:
Installed: 2.11-1.1+1.1
Candidate: 2.11-1.1+1.1
Version table:
1:0.88-6 500
500 http://raspbian.raspberrypi.org/raspbian buster/main armhf Packages
*** 2.11-1.1+1.1 1001
1001 http://download.opensuse.org/repositories/home:/indimail/Debian_10/ Packages
100 /var/lib/dpkg/status