Guides 11792 Published by Philipp Esselbach 0

The article explains how the dd command can create bootable USB drives from ISO files by writing raw data block by block and thus producing exact disk copies. It guides readers through finding the right device path with tools such as fdisk or lsblk, unmounting any partitions to avoid accidental overwrites, and then running dd with a 4 MB block size, progress status, and fsync for safety and speed. The writer stresses that interrupting the process can leave a corrupted drive, recommends verifying the result with testdisk or SHA‑256 checksums, and cautions about the lack of capacity checking in dd. While noting that user-friendly tools exist for most users, it advises reserving dd for situations where precise binary fidelity is required and urges double-checking image size against device capacity to prevent data loss.

Guides 11792 Published by Philipp Esselbach 0

When APT starts complaining that a signing key has expired, the root cause is usually an old GPG key lingering in /etc/apt/trusted.gpg.d. You can spot which keys are past due by running “sudo apt-key list” and grepping for expires or expired to note their fingerprints. Removing the key is straightforward: if you still have apt‑key, delete it with “sudo apt-key del ”; on newer systems replace the source line’s signed‑by reference to a fresh key file and then remove the obsolete one. After cleaning any remnants, run “sudo apt update” and the warning will vanish—essentially just list expired keys, delete them, adjust repository entries, and refresh APT.

Guides 11792 Published by Philipp Esselbach 0

The article serves as an accessible guide to managing Linux services through the systemctl command, offering a quick‑look cheat sheet for common operations and explaining why each command matters. It walks readers through starting, stopping, restarting, reloading, enabling, disabling, and checking the status of services while also illustrating how logs can be examined with journalctl for troubleshooting. The piece clears up misconceptions about systemd versus older init systems and shows how legacy scripts are still under systemctl control, adding practical tips such as masking to block unwanted units. Overall it aims to demystify service management so users feel confident keeping their Linux machines running smoothly without the headache of hidden daemons.

Guides 11792 Published by Philipp Esselbach 0

KernelCare lets you patch the Linux kernel without rebooting, and this article walks through how to set it up on both Debian‑based and RHEL‑based distributions while also showing a quick way to wipe its cache. On Ubuntu or Debian you first download a signed installer script that adds an APT repository, then run the key command with your personal API key before enabling the kernelcare.service at boot so it automatically starts after each restart. For CentOS and RHEL, the same shell script configures YUM, followed by registering the key with kernelcare-apikey and starting the service; once running you can stop it, delete everything in /var/cache/kernelcare to reclaim space, and restart so fresh patches are fetched again. If connectivity fails or the daemon is unintentionally disabled after an upgrade, re‑enable it and check proxy settings, while a real‑world example showed that clearing the cache resolved a kernel module load failure after a power loss.