If you are using Raspbian GNU/Linux 9 (stretch), then you are most likely using dhcpcd as your DHCP and DHCPv6 client. How to know your OS version? Here :

• dhcpcd gets the host information (IP address, routes, etc) from a DHCP server and configures the network interface of the machine on which it is running. Manual of DHCPCD(8).

• dhcpcd-run-hooks is a DHCP client configuration script. It is used by dhcpcd to run any system and user defined hook scripts. Manual of DHCPCD-RUN-HOOKS(8).

dhcpcd

It seems that to restart all network interfaces this works :

To understand what happened, better read dhcpcd logs, here is what we can see:

Source

dhcpcd-run-hooks

dhcpcd runs /lib/dhcpcd/dhcpcd-run-hooks. This script runs each script found in /lib/dhcpcd/dhcpcd-hooks in a lexical order.
dhcpcd-run-hooks is used by dhcpcd to run any system and user defined hook scripts. System hook scripts are found in /lib/dhcpcd/dhcpcd-hooks.
There is a list of reasons why dhcpcd-run-hooks could be invoked, such as BOUND (= dhcpcd obtained a new lease from a DHCP server = computer has an IP assigned on the interface).
Many variables will then be set, along with any protocol supplied ones, such as :

• $interface : the name of the interface
• $reason : reason why dhcpcd-run-hooks was invoked
• $if_up : true if the interface is up, otherwise false.

To know what is the current IPv4 address after an interface BOUNDed dhcpcd obtained a new lease from a DHCP server.:

I created /lib/dhcpcd/dhcpcd-hooks/60-test_by_pmd in order to play with this functionality. Shell script I used in order to check IP after new DHCP lease was obtained (writing output in /home/pi/test.txt in order to see what happened afterward):

Sources : both manuals.

It happens that NordVPN openvpn configuration files don't work anymore after a while.

I made a bash script to update the configuration easy and fast:

Then simply execute the script:

If your airsonic is stucked for some reasons such as Liquibase Update Failed and Waiting for changelog lock...

1. Stop Airsonic for sure :
   sudo service airsonic stop
2. Read logs /var/airsonic/airsonic.log :
   nano /var/airsonic/airsonic.log
3. Backup your database folder /var/airsonic/db :
   sudo cp /var/airsonic/db /var/airsonic/db_backup
4. Edit /var/airsonic/db/airsonic.script :
   sudo nano /var/airsonic/db/airsonic.script
   • remove all lines where you can find DATABASECHANGELOGLOCK by example :
     • CREATE MEMORY TABLE DATABASECHANGELOGLOCK.....
     • INSERT INTO DATABASECHANGELOGLOCK VALUES(1,TRUE,'2018-11-18 16:39:56.266000000','192.168.254.200 (192.168.254.200)')
5. Save file.
6. Start Airsonic :
   sudo service airsonic start
7. Check Airsonic status :
   sudo service airsonic status

If you wanna reset your Airsonic music server, just delete the database /var/airsonic/db ...

Source 1, 2, 3.

How to update a standalone Airsonic

• Stop the current running Airsonic:

• Go to the Airsonic folder, backup the old airsonic.war file, and download the new one. Check what is the last version: https://airsonic.github.io/download/

• Put good rights to all folder (new airsonic.war is not owned by airsonic), and verify it has been applied:

• Start updated Airsonic and restart proxy server:

Nothing too hard, basically, you need to replace the airsonic.war by the updated one.

PluXml 5.6 / CKEditor 4.7.3 modification to get handy code <div>

I modified the file /plugins/ckeditor/ckeditor/styles.js to have a much more easier way to put code in my memo.

Before:

After:

Modification to get better visual when using <kbd>

In PluxXML Administration > Parameters > Themes > Edit Theme files > /css/plucss.css I have set this for <kbd> HTML tag.

• Before : CTRL + ALT + DEL
• After : CTRL + ALT + DEL

CSS source

Original post

I am loosing connection to my Raspberry Pi 3 in a very much random way.

I recently replaced Subsonic by Airsonic, and connection to Pi seemed to be much more stable since that exact day. But today, it happened one more time... as I was expecting! Time to troubleshoot has come.

Since I am using 2 tables to root my traffic, one of them is not updated on some interface up/down events. I made a small script called by cron every 5 minutes to understand things and rebooting Pi once a day to get the access back:

Time when it got fucked:

I then checked /var/log/syslog:

After Googling, I found an interesting article. Which provide interesting tips.

1. Use this command to read the current power saving mode of your Pi:
   $ sudo iw wlan0 get power_save
   Power save: on
2. And this one to turn power_save off:
   $ sudo iw wlan0 set power_save off
3. To make this permanent add the following line to /etc/rc.local:
   /sbin/iw dev wlan0 set power_save off

We will see if it helps :)

Update 27/10/2018

I choose to turn the power_save off as it originally was. But I came up with this script:

I run this script every 5 minutes, line in my crontab file:

Log file looks like this:

youtube-dl is a usefull packet to download youtube video through command line. GitHub.

List what to download

First step is to list what youtube video you wanna download and convert to mp3 file:

2 files to put on a web server which are:

1. liste.txt which must be chmod 777 (index.php will write links in this file)
2. index.php

Sources 1, 2

Secure input form

https://docs.nginx.com/nginx/admin-guide/security-controls/configuring-http-basic-authentication/
http://www.htaccesstools.com/htpasswd-generator/

Restart nginx:

Download script

He depends on:

• /path/to/liste_en_cours.txt
• /path/to/history.txt

Source homemade. Now execute it with cron job by example.

Switching to yt-dlp

youtube-dl is notmaintained anymore. It now fails with "Unable to extract uploader id" error using version 2021.12.17. yt-dlp is a youtube-dl fork based on the now inactive youtube-dlc. The main focus of this project is adding new features and patches while also keeping up to date with the original project.

Use SSH to connect to Raspberry Pi. Run the following command to download the latest version of yt-dlp from GitHub repository:

Set read and execute permissions for a file:

Now yt-dlp command will be available for all users as a system-wide command.
We can check yt-dlp version as follows:

We can update yt-dlp to the latest version by using the following command:

So in above script I replace /usr/local/bin/youtube-dl by /usr/local/bin/yt-dlp.

Source.

Stand-alone WAR installation integrated within systemd

Let's see how to install a stand-alone Airsonic on a Raspberry 3 integrated with Systemd.

First of all, we need Java to be installed:

By following these systemd setup instructions, Airsonic will be available at http://localhost:8080/airsonic.

1. Setup dedicated airsonic user:
   $ sudo useradd airsonic
2. Setup Airsonic data dir:
   $ sudo mkdir /var/airsonic
   $ sudo chown airsonic /var/airsonic
3. Download the stand-alone WAR:
   $ sudo wget https://github.com/airsonic/airsonic/releases/download/v10.1.1/airsonic.war --output-document=/var/airsonic/airsonic.war
4. Setup systemd service:
   $ sudo wget https://raw.githubusercontent.com/airsonic/airsonic/master/contrib/airsonic.service -O /etc/systemd/system/airsonic.service
   $ sudo systemctl daemon-reload
   $ sudo systemctl start airsonic.service
   $ sudo systemctl enable airsonic.service
   $ sudo wget https://raw.githubusercontent.com/airsonic/airsonic/master/contrib/airsonic-systemd-env -O /etc/sysconfig/airsonic

   Note: On Debian systems you need to replace /etc/sysconfig with /etc/default)

5. Go configure http://localhost:8080/airsonic.

Set up a reverse proxy: nginx

1. Go edit nginx configuration:
   $ sudo nano /etc/nginx/sites-available/default
2.         location ^~ /airsonic {
                   proxy_pass http://127.0.0.1:8080;
                   proxy_set_header Host $host;
                   proxy_set_header X-Real-IP $remote_addr;
                   proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
           }
3. Restart nginx:
   $ sudo service nginx restart

Now the Airsonic server should be accissible from outside uside http://publicadress.com/airsonic

Source 1 : Stand-alone WAR installation
Source 2 : The url I'm opening is http://publicadress.com/airsonic but it will be redirected to http://publicadress.com/login, which brings up error 404.

Set up the transcoder

Then we need to link Airsonic with the transcoder ffmpeg.

Interact with server from Android

I use the Ultrasonic application:

Source 1, 2, 3,

Startup log example

Transmission

1. opkg update
2. opkg install transmission-daemon-openssl transmission-web luci-app-transmission
3. opkg install nano
4. nano /etc/config/transmission
5. chmod -R 777 /tmp/USB_KEY

It is necessary to make a swap file on AR150 otherwise you cannot access the web interface...

1. cd /path/where/we/will/make/swap-file
2. Create a 64MB swap-file:
   dd if=/dev/zero of=swap-file bs=1M count=64
3. mkswap swap-file
4. swapon swap-file
5. Then go to LuCI to specify the swap file in System > Mount points to have it mounted at next router reboot.

For worldwide access add a rule in LEDE firewall:
Any tcp, udp
From any host in wan
To any router IP at port 9091 on this device

Source

Bandwidth Monitor (nlbw)

Aussi :

https://github.com/Kiougar/luci-wrtbwmon

How to upgrade GL-AR150 to Stock OpenWRT

1. Connect to router using SSH
2. # cd /tmp
3. Check what is the last available release for GL-AR150 here.
4. # wget http://downloads.lede-project.org/releases/17.01.4/targets/ar71xx/generic/lede-17.01.4-ar71xx-generic-gl-ar150-squashfs-sysupgrade.bin
5. # sysupgrade lede-17.01.4-ar71xx-generic-gl-ar150-squashfs-sysupgrade.bin

Source

I installed this version: LEDE Reboot (17.01.4, r3560-79f57e422d).

How to upgrade all packets

Sources 1, 2

Enabling remote SSH access on LEDE/OpenWRT

Configure Dropbear

1. Go to the System / Administration page.
2. Under “SSH Access”, for the default “Dropbear instance”, set “Interface” to “unspecified”.

This will cause dropbear to accept connections on all interfaces.

Open port 22 (or other)

1. Go to the Network / Firewall / Traffic Rules.
2. Scroll down to the “Open ports on router” section.
3. Enter a name for this rule, e.g. “Allow-SSH-WAN”.
4. Set “Protocol” to “TCP”.
5. Enter “22” as the “External Port”.
6. Click “Add”.
7. Click “Save and Apply”.

Source

Using USB storage devices and FAT32&NTFS filesystems

1. Connect to router using SSH
2. # opkg update
3. # opkg install kmod-usb-storage
4. # opkg install usbutils
5. # lsusb -t
   /: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=ehci-platform/1p, 480M
      |__ Port 1: Dev 2, If 0, Class=Mass Storage, Driver=usb-storage, 480M
6. To add support of FAT32 and NTFS (not tested yet) usb flash/disk drives:
   # opkg install kmod-fs-vfat ntfs-3g
7. Then go to the LuCI administration page, System > Mount points, and configure :
   

Sources 1, 2, 3, 4, 5

Using the Huawei E3372 Hi-Link LTE Dongle with OpenWRT

Huawei E3372 and AR-150 have 192.168.8.1/24 IPv4 networks, change the LAN IP of AR-150.

1. # opkg update && opkg install kmod-usb-net-rndis usb-modeswitch
   Of course, an internet connection is needed through Ethernet or Wifi for this step. :(
2. Then go to the LuCI administration page, Network > Interfaces > Add new interface...:
   
3. In my case interface "eth2" is now available to configure:
   
4. In tab Firewall Settings, add this new interface in the wan firewall-zone:
   
5. Click on Connect of the new network 4G_LTE:
   
6. Done, you even have access to the USB dongle administration page 192.168.8.1.

Source Nouvelle source (2020-02)

DDNS

1. # opkg install luci-app-ddns
2. Go to LuCI administration interface > Services > Dynamic DNS.
3. I used a Free DNS provider named freedns.afraid.org.

Source

Samba network share

1. # opkg install luci-app-samba
2. Go to LuCI administration interface > Services > Network Shares.
3. Add shared directories:
   • Name: samba
   • Path: /Path/to/mounted/usb/key
   • Allowed user: empty
   • Create mask: 777
   • Directory mask: 777

Source

SFTP server

1. # opkg update && opkg install openssh-sftp-server
2. Use Filezilla or other to connect to sftp server.

Source