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David Cao

David is a Cloud & DevOps Enthusiast. He has years of experience as a Linux engineer. He had working experience in AMD, EMC. He likes Linux, Python, bash, and more. He is a technical blogger and a Software Engineer. He enjoys sharing his learning and contributing to open-source.

The df command in linux displays the amount of disk space used and available on Linux file systems. If this command is hanging or not responding, it might be due to one of the following reasons: 1. Network File System (NFS) mounts that are not responding. If you have any networked drives or directories and …

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The error “Unable to negotiate with host port 22: no matching MAC found. Their offer: hmac-sha2-512,hmac-sha2-256” indicates that there’s a mismatch in the MAC (Message Authentication Code) algorithms supported by the client and the server during an SSH connection attempt. In this article, we will share how to fix this issue. How to fix no …

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SSH (Secure Shell) is a vital tool for remote administration and file transfer in many Linux environments. However, if not properly secured, SSH can be a potential gateway for unauthorized access and malicious activities. By adhering to the following best practices, you can enhance the security of your SSH server. 1. Use SSH Protocol Version …

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The error message `channel 3: open failed: administratively prohibited: open failed` typically appears when trying to use SSH tunneling (port forwarding) and the server is not configured to allow this or is actively blocking it. Here’s how to fix it: 1. Server Configuration: First and foremost, make sure your SSH server is configured to allow …

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Secure Shell (SSH) is a cryptographic network protocol that plays a vital role in secure data communication, remote command-line login, and remote command execution. One of the core components of SSH’s security model is its use of Message Authentication Code (MAC) algorithms. MAC algorithms ensure data integrity and authenticity between the SSH client and server. …

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Linux is renowned for its flexibility and the wide array of software applications available for it. However, managing software installations, updates, and removals can be a complex task. This is where package managers come to the rescue. In this comprehensive guide, we will delve into the world of package management in Linux, exploring its significance, …

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Linux provides a range of network configuration tools, from traditional ones like ifconfig and route to modern alternatives such as ip, nmcli, and nmtui. The choice of tool typically depends on the specific Linux distribution and the administrator’s preferences. NetworkManager and systemd-networkd have revolutionized network management by offering both command-line (CLI) and graphical (GUI) tools …

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The Qualys Threat Research Unit (TRU) recently uncovered a buffer overflow vulnerability within the GNU C Library’s dynamic loader, specifically in how it handles the GLIBC_TUNABLES environment variable. Their team has detected and exploited this vulnerability. When exploited, it leads to a local privilege escalation granting full root privileges. This vulnerability affects default installations of …

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In the dynamic landscape of technology, Linux has remained a steadfast and influential player for decades. As the digital world continues to evolve, Linux’s role in shaping emerging technologies cannot be understated. In this article, we embark on a journey to explore how Linux is leaving its indelible mark on emerging technologies and what lies …

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Linux servers are the backbone of many critical systems and services, powering everything from web applications to databases and cloud infrastructure. As a system administrator, ensuring the security of these servers is paramount. Cyber threats are constantly evolving, and vulnerabilities can be exploited if not properly addressed. In this article, we’ll explore Linux server security …

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