Tag: ubuntu

Disable systemd-networkd-wait-online.service in Ubuntu Server

In Ubuntu Server, the systemd-networkd-wait-online.service is responsible for waiting until the network is fully online before allowing the boot process to continue. This service can sometimes cause delays during the boot process if the network configuration takes a long time to initialize.

1. Disable the Service

To completely disable the systemd-networkd-wait-online.service, run the following command:

sudo systemctl disable systemd-networkd-wait-online.service

This will prevent the service from starting at boot time.

2. Mask the Service (Optional)

If you want to ensure that the service cannot be started manually or automatically by any other service, you can mask it:

sudo systemctl mask systemd-networkd-wait-online.service

Masking creates a symbolic link to /dev/null, making it impossible for the service to start unless explicitly unmasked.

Install Syncthing on Ubuntu 24.04

# Add the release PGP keys:
sudo mkdir -p /etc/apt/keyrings
sudo curl -L -o /etc/apt/keyrings/syncthing-archive-keyring.gpg https://syncthing.net/release-key.gpg
# Add the "stable" channel to your APT sources:
echo "deb [signed-by=/etc/apt/keyrings/syncthing-archive-keyring.gpg] https://apt.syncthing.net/ syncthing stable" | sudo tee /etc/apt/sources.list.d/syncthing.list
# Update and install syncthing:
sudo apt-get update
sudo apt-get install syncthing

Syncthing can be run as a service so that it starts automatically on boot.

  1. Enable the Syncthing service : By default, Syncthing installs a systemd service for the user syncthing. You can enable it to start on boot. 
    sudo systemctl enable syncthing@<username>.service

    Replace <username> with the username of the user who will run Syncthing. For example, if your username is ubuntu, the command would be:

    sudo systemctl enable syncthing@ubuntu.service
  2. Start the Syncthing service : Once enabled, start the Syncthing service. 
    sudo systemctl start syncthing@<username>.service

By default, Syncthing runs on localhost and listens on port 8384.

References
https://apt.syncthing.net/

Manually set the time on an Ubuntu server

1. Check the current time

Before setting the time, check the current system time by running:

timedatectl

This will display information about your system’s time and time zone.

2. Set the time manually

To set the time manually, use the timedatectl command in the following format:

sudo timedatectl set-time "YYYY-MM-DD HH:MM:SS"

For example, to set the date and time to October 12, 2024, 19:30:00, you would run:

sudo timedatectl set-time "2024-10-12 19:30:00"

3. Disable automatic time synchronization (if needed)

If your server is using NTP (Network Time Protocol) for automatic time synchronization, you may need to disable it before setting the time manually. To do this, run:

sudo timedatectl set-ntp off

4. Verify the new time

After setting the time, you can verify it with:

timedatectl

This will show the updated time and any other related settings.

Update Kernel arguments for better performance in Ubuntu 24.04

Here’s how you can apply these kernel parameters in Ubuntu 24.04:

  1. Edit GRUB Configuration File:

    Open the GRUB configuration file in a text editor. For example, you can use nano:

    sudo nano /etc/default/grub
  2. Add Kernel Parameters:

    Find the line that starts with GRUB_CMDLINE_LINUX_DEFAULT and add your parameters to the list. It should look something like this:

    GRUB_CMDLINE_LINUX_DEFAULT="quiet splash mitigations=off mem_sleep_default=s2idle nvidia-drm.modeset=1"

    Ensure that all parameters are enclosed within the same set of quotes.

  3. Update GRUB:

    After saving the changes, you need to update the GRUB configuration:

    sudo update-grub
  4. Reboot:

    Finally, reboot your system to apply the changes:

    sudo reboot

This will apply the desired kernel parameters on all boot entries.

Install Android ADB on Ubuntu Linux

To install Android ADB (Android Debug Bridge) on Ubuntu, you can follow these steps:

Identify the Vendor ID:

Connect your Android device to your computer and run the following command to identify the vendor ID:

lsusb

Look for the line that corresponds to your Android device. The vendor ID is the first part of the ID after ID, for example, 18d1 for Google.

Update Your Package List: Open your terminal and update the package list to ensure you have the latest information on the newest versions of packages and their dependencies.

sudo apt update

Install ADB: You can install the ADB package using the following command:

sudo apt install android-tools-adb

Verify Installation: After installation, you can verify that ADB is installed correctly by checking its version:

adb version

Add Your User to the Plugdev Group (Optional): This step ensures that you can use ADB without root permissions. It’s especially useful when working with devices.

sudo usermod -aG plugdev $USER

Then, log out and log back in to apply the changes.

Set Up Udev Rules (Optional): To communicate with your Android device over USB, you might need to set up udev rules. Create a new udev rules file:

sudo nano /etc/udev/rules.d/51-android.rules

Add the following line to the file, replacing xxxx with your device’s USB vendor ID (you can find a list of these IDs online or in the documentation for your device):

SUBSYSTEM=="usb", ATTR{idVendor}=="18d1", MODE="0666", GROUP="plugdev"

Save and close the file, then reload the udev rules:

sudo udevadm control --reload-rules

Now, you should have ADB installed and configured on your Ubuntu system. You can connect your Android device and start using ADB commands.

Using Data Recovery Tools in Linux

Stop Using the Drive

Immediately stop using the drive to prevent further data overwriting.

Identify the Overwritten Part

Determine how much data the ISO has overwritten. Typically, writing an ISO will overwrite the beginning of the drive, including the partition table and some initial sectors.

Use Data Recovery Tools

You can try using data recovery tools that work well on Linux:

  1. TestDisk: This tool can help recover lost partitions and make non-booting disks bootable again. It can also recover deleted files from FAT, NTFS, and ext2 filesystems.
  2. PhotoRec: This companion tool to TestDisk specializes in recovering lost files, including videos, documents, and archives from hard disks, CD-ROMs, and lost pictures from memory cards.
  3. ddrescue: A data recovery tool specifically designed to recover data from damaged disks. It can create a disk image and then work on the image to recover data.

Steps to Recover Data

  1. Install Recovery Tools: 
    sudo apt-get install testdisk photorec gddrescue
  2. Create a Disk Image: It’s safer to work on a disk image rather than directly on the hard drive. 
    sudo ddrescue /dev/sdX /path/to/image.img /path/to/logfile.log

    Replace /dev/sdX with your external hard drive’s identifier.

  3. Run TestDisk: 
    sudo testdisk /path/to/image.img

    Follow the on-screen instructions to analyze and recover lost partitions.

  4. Run PhotoRec: 
    sudo photorec /path/to/image.img

    This will guide you through recovering individual files.

Set Battery Charge Limit in Ubuntu

ls /sys/class/power_supply/

ls /sys/class/power_supply/BAT0

sudo sh -c "echo 60 > /sys/class/power_supply/BAT0/charge_control_end_threshold"

cat /sys/class/power_supply/BAT0/status

Create Battery Charge Threshold Service

sudo nano /etc/systemd/system/battery-charge-end-threshold.service

[Unit]
Description=Set Battery Charge Maximum Limit
After=multi-user.target
StartLimitBurst=0

[Service]
Type=oneshot
Restart=on-failure
ExecStart=/bin/bash -c 'echo 60 > /sys/class/power_supply/BAT0/charge_control_end_threshold'

[Install]
WantedBy=multi-user.target
sudo systemctl enable battery-charge-end-threshold.service

sudo systemctl daemon-reload

sudo systemctl start battery-charge-end-threshold.service

References
https://ubuntuhandbook.org/index.php/2024/02/limit-battery-charge-ubuntu/