#ziktips — Public Fediverse posts

💡 TIP: On a Linux system using bash, you can compare text strings without worrying about upper or lowercase by using the ,, (lowercase) or ^^ (uppercase) parameter expansion modifiers e.g.

EDITION=CommUNITY

if [[ ${EDITION,,} = community ]]; then
echo "Community"
fi

${EDITION,,} converts the value to lowercase.

@opensuse @fedora @debian
#ZikTIPs #bash #scripting #linuxtips #techtips #feditips #Linux #opensource

💡 Calculate the number of days since a given date (e.g. 30 June 2025) on a Linux system:

echo $(( ( $(date +%s) - $(date -d "2025-06-30" +%s) ) / 86400 ))

@opensuse @fedora @debian #ZikTIPs #Linuxtips #LinuxTechTips #Linux #FOSS #Opensource

💡Use iperf3 to measure the network throughput between two Linux nodes effortlessly as follows: @fedora @opensuse

On server: iperf3 -s

On client: iperf3 -c <SERVER_IP>

#ZikTIPS #Linuxtips $Networking #LinuxTechTips #Linux #Opensource

💡 Record audio from a microphone on a Linux system using gstreamer @gstreamer @fedora @opensuse @archlinux

gst-launch-1.0 alsasrc ! audioconvert ! lamemp3enc ! filesink location=recorded.mp3

#ZikTIPs #pipewire #pulseaudio #techtips #Linuxtips #LinuxTechTips #Linux #Opensource

💡 Use the following Linux command to create a file with a specific access and modification timestamp @fedora @opensuse @archlinux

touch -t [FILE]

e.g. For a file named mytalk.txt March 10, 2025 at 9AM:

touch -t 202503100900 mytalk.txt

To verify:
stat -c "%x%y" mytalk.txt.

#ZikTIPs #Linuxtips #LinuxTechTips #Linux #Opensource

TIP: 💡Check the remaining battery level for your connected bluetooth device on a typical Linux system using the following command:

bluetoothctl info AA:BB:CC:DD:00:11 | awk '/Battery Percentage:/ {print $4}' | tr -d '()'

* Replace "AA:BB:CC:DD:00:11" with the MAC address of your bluetooth device

@openSUSE  @fedora @debian  #ZikTIPS #Bluetooth #Audio #TechTips #SysAdmin #LinuxTips #CLI #OpenSUSE #Fedora #Debian #Linux #opensource

💡 On a typical Linux system, you can find bluetooth devices that are paired, connected, and trusted using the following command line:

bluetoothctl devices [ Paired | Connected | Trusted ]

For example: List currently paired bluetooth devices:

$ bluetoothctl devices Paired

Device 00:42:XX:YY:ZZ:YY XXBK85
Device 00:FD:AA:XX:YY:X8 D-26

@opensuse @fedora @debian #ZikTIPS #TechTips #SysAdmin #LinuxTips #CLI #OpenSUSE #Fedora #Debian #Linux #opensource

For anyone interested in using Kea DHCP server on buildroot, I have submitted a new package patch that is currently awaiting upstream review. You can check it out here:

https://patchwork.ozlabs.org/project/buildroot/patch/[email protected]/

@iscdotorg
#ZikTIPS #buildroot #dhcp #networking #linux #opensource

💡Did you know you can just run the mount command with -m flag to create a non-existent mount point instead of first creating it.

e.g. mount -m /dev/sdc1 /myflash

#ZikTIPs #linuxtips #techti #Linux #OpenSource

💡 It's conference 🎤 season! Impress your audience with a slick QR code using these easy commands on Linux

✅ Add your content to a text file:
printf " Name: Zik Joseph\n Blog: https://zikusooka.com \n" > my_contacts.txt

✅ Convert text file (and contents) into QR code image:
qrencode -o zik.png -r my_contacts.txt

Thats all! Add zik.png to your slides. Easy, classy.

#ZikTIPS #TechTips #LinuxTips #Conference #Linux #FOSS #OpenSource

💡 Use the following command line to generate a list of security advisories on Fedora and RedHat Linux based systems #ZikTIPs #TechTips #Fedora #Redhat #Linux #Security #Opensource
@fedora @redhat

sudo dnf advisory list

If you’re like me and enjoy watching streams or listening to multiple audio sources, check out my newly updated @pipewire based script! It makes muting or unmuting sound from different sources really easy.

Find it here:
https://github.com/zikusooka/toggle-pw-volumes
Context: https://joseph.zikusooka.com/?p=2637

#ZikTIPs #Linux #PipeWire #Multimedia

Cheat sheet: How to easily manage your packages using the Zypper command line tool on #OpenSUSE #Linux @opensuse #techtips #ZikTIPS

https://en.opensuse.org/images/3/30/Zypper-cheat-sheet-2.pdf

💡On a Linux system, use the "nohup" utility to execute one-time commands or scripts that can run later, even after you log out of your terminal session @opensuse
@fedora @debian

Example: To schedule a one-time script to run 15 minutes after you disconnect from the terminal:

nohup bash -c "(sleep 900 && ./myscript.sh)" &

#ZikTIPS #linuxtips #techtips #sysadmin #Fedora #OpenSUSE #Linux #Opensource

💡 You can simultaneously query multiple domain name records using the dig command in Linux as follows:

dig OPTIONS @server -f BATCH_FILE

Example:
dig +nocmd +noquestion +nostats +nocomments @8.8.8.8 -f mydomains.txt

cat mydomains.txt
example.com A
example.net MX
example.org NS

TIP: dig is part of the dns/bind utilities package depending on your distribution

#ZikTIPS #DNS #Bind #SysAdmins #CLI #Linux #Opensource

💡 To display a full list of known users on a Linux system, use the following command @fedora @opensuse @debian @ubuntu

lslogins

#ZikTIPS #Sysadmin #CLI #Fedora #OpenSUSE #Linux #opensource #TipsTech

🎉 Excited to share HASS Core Installer, a tool that simplifies installing and upgrading Home Assistant Core in a Python 3 virtual environment! @homeassistant @jambulatv @jambula

🚀 Works online & offline, complementing existing methods for diverse setups.

🥦 Check it out on GitHub:
https://github.com/zikusooka/hass-core-installer

#HomeAssistant #SmartHome #ZikTIPs #Linux #opensource

💡To display the DHCP IPv4 options assigned to a Linux client, use the following command line @opensuse @fedora @NetworkManager #ZikTIPs #CLI #Networking #Linux #OpenSource

nmcli -f DHCP4 device show "$INTERFACE"

e.g. nmcli -f DHCP4 device show eth0

💡 Use the 'lsof' command to quickly identify the ports that a specific service is listening on within a Linux system @opensuse @fedora @climagic

Example:
SERVICE=sshd; lsof -i -P -n | grep $SERVICE | awk '/LISTEN/ {print $9}' | uniq

#ZikTIPs #SysAdmins #Linux #Opensource

💡 Use the following command to quickly check how much space you have left on your Linux filesystem
@opensuse @fedora @debian #ZikTIPs #Linux #CLI #Opensource #linux

df -h --output=avail /

💡 If you have SELinux enabled on your Linux system, you can view the context of an object as follows @opensuse @fedora #ZikTIPS #Sysadmin #SELinux #CLI #OpenSUSE #Linux

For a file:
ls -Z [FILE] e.g.
ls -Z /etc/selinux/config

For a process:
ps -eZ | grep [PROCESS_NAME] e.g.
ps -eZ | grep apache2

💡Get the inode number of a file using this simple command line on Linux @opensuse @fedora @archlinux

ls -i [FILENAME] e.g.

ls -i /etc/fstab

#ZikTIPs #CLI #Fedora #OpenSUSE #Debian #Linux #opensource

💡 Display a list of all users on a Linux system using the following command @opensuse @fedora @ubuntu #ZikTIPs #CLI #Fedora #OpenSUSE #Ubuntu #Linux #opensource

getent passwd | cut -d ":" -f1

💡 Quickly inspect the contents of a systemd unit file in Linux using the following command #ZikTIPS #CLI #Fedora #Ubuntu #Linux #Opensource
@opensuse @fedora @debian

systemctl cat [UNIT] e.g.

systemctl cat sshd.service

💡Display the active WiFi connection using the following command in Linux #ZikTIPs #CLI #WiFi #Linux #Opensource
@NetworkManager @opensuse @fedora @debian

nmcli connection show --active

NOTE: Works on distributions that use #networkmanager

💡️On a Linux system, you can retrieve logging information for a specific service within a designated date range
#ZikTIPS #CLI #Systemd #Linux #Opensource @fedora @opensuse

journalctl -u [UNIT] -S [DATE-START] -U [DATE-END]

e.g.
journalctl -u sshd -S 2024-10-04 -U 2024-10-12

💡 Search for webcams on a Linux system using the following command line @fedora @opensuse #ZikTIPS #Linux #CLI #Multimedia #Video #Audio #Opensource

v4l2-ctl --list-devices

💡️ Display the actual target path of a symbolic link in Linux
#ZikTIPs #CLI #Linux #Opensource

readlink -f [LINK]

💡️Quickly change the bluetooth name advertised by your Linux device such as a raspberrypi @debian @opensuse @fedora

bluetoothctl system-alias "NEW-NAME"

#ZikTIPs #Bluetooth #Raspberrypi #Linux #Opensource

💡Remove or replace multiple occurrences of text with a similar pattern using the command line in Linux

sed /PATTERN*//g [FILE_PATH]

Example:
sed /systemd-network*//g /opt/my script.sh

#ZikTIPs #SysAdmin #CLI #Linux #Opensource #opensourcesoftware

💡Use the Linux command line to launch a live Youtube stream e.g. To watch the on-going @fedora @fedora_design #CreativeFreedomSummit

streamlink https://www.youtube.com/watch?v=sUrTAyksmHA best

#ZikTIPS #CLI #Fedora #Linux