How can I find the correct ulimit values for a user account or process on Linux systems? Love this? sudo share_on: Twitter - Facebook - LinkedIn - Whatsapp - Reddit The post How to find ulimit for user on Linux appeared first on nixCraft. 2024-05-16T21:57:31Z 2024-05-16T21:57:31Z Vivek Gite

A Ubuntu 24.04 LTS comes with UFW (uncomplicated firewall) that protects the desktop or server against unauthorized access. UFW is an easy-to-use frontend app for a Linux packet filtering system called Netfilter or nftables. Traditionally, Netfilter/nftables rules are set up or configured using the iptables command or nft command by developers and sysadmins. However, new Ubuntu Linux users and developers unfamiliar with firewall concepts find Netfilter/nft syntax confusing. Hence, the ufw project provides an easy-to-use frontend for Ubuntu 24.04 LTS Linux server and desktop. This quick guide makes setting up UFW on Ubuntu 24.04 LTS extremely simple. It provides step-by-step instructions for developers and sysadmins to secure their servers efficiently. Love this? sudo share_on: Twitter - Facebook - LinkedIn - Whatsapp - Reddit The post How to Set Up UFW Firewall on Ubuntu 24.04 LTS in 5 Minutes appeared first on nixCraft. 2024-05-15T10:09:51Z 2024-05-15T10:09:51Z Vivek Gite

I have log files created whenever I patch or rebuild Linux containers. They are taking disk space. The logs are helpful if something fails. Otherwise, after a few weeks, those log files have no usage for me. So here is a quick tip on how to use the find command to delete all *.log files created in the last 90 days except for the previous 7 or 10 days. The commands mentioned in these tips are compatible with the Linux, FreeBSD, and macOS versions of the find command. Love this? sudo share_on: Twitter - Facebook - LinkedIn - Whatsapp - Reddit The post How to use find command to delete all *.log files created in last 90 days except for last 7 days appeared first on nixCraft. 2024-05-15T06:56:03Z 2024-05-15T06:56:03Z Vivek Gite

An IP alias on Debian, Ubuntu, or any other Linux distros refers to assigning multiple IP addresses to a single network interface. A single network interface card (NIC) can respond to multiple IP addresses and configurations. IP aliases are commonly used for various purposes, such as network segmentation, virtual hosting, load balancing, VPN, split DNS, network testing, and more. Let us see how to add IPv6 and IPv4 IP addresses to your AWS EC2 or Lightsail instance using the CLI without disturbing the IPv4/IPv6 addresses assigned by the AWS DHCP server. These instructions will also work with all other cloud providers, as most providers use DHCP to give you a public IPv4/IPv6 address. Love this? sudo share_on: Twitter - Facebook - LinkedIn - Whatsapp - Reddit The post How to add an IP alias to an EC2 instance on Debian/Ubuntu Linux appeared first on nixCraft. 2024-05-14T20:43:57Z 2024-05-14T20:43:57Z Vivek Gite

DNSCrypt-proxy is an open-source and free software designed to encrypt DNS traffic, thus protecting it from eavesdropping and manipulation. This is also useful to evade DNS censorship when DNSCrypt-proxy is configured correctly with Wireguard or OpenVPN. Further, DNSCrypt-proxy can configured to block malware, trackers, and internet ads. In Debian 11 and 12, using DNSCrypt-proxy can enhance privacy and security by preventing DNS spoofing attacks, DNS hijacking, and surveillance of DNS traffic. It ensures that DNS queries are encrypted, authenticated, and secure, thereby safeguarding users' browsing activities and sensitive information. Let us see how to install dnscrypt-proxy on Debian Linux 11 and 12. Love this? sudo share_on: Twitter - Facebook - LinkedIn - Whatsapp - Reddit The post How to install dnscrypt-proxy on Debian Linux 11/12 appeared first on nixCraft. 2024-05-13T12:23:14Z 2024-05-13T12:23:14Z Vivek Gite

I am a new macOS Unix user. I am writing a small bash shell script. How do I download file directly from the command-line interface using curl? How can I download file with cURL on a Linux or Unix-like systems? Love this? sudo share_on: Twitter - Facebook - LinkedIn - Whatsapp - Reddit The post How to download a file with curl on Linux/Unix command line appeared first on nixCraft. 2024-05-12T19:41:44Z 2024-05-12T19:41:44Z Vivek Gite

I am a new Linux user. How do I display the process on the Linux based server or desktop/laptop in easy to read tree format using bash shell prompt? Love this? sudo share_on: Twitter - Facebook - LinkedIn - Whatsapp - Reddit The post Linux/Unix: pstree Command Examples: See A Tree Of Processes appeared first on nixCraft. 2024-05-12T19:29:49Z 2024-05-12T19:29:49Z Vivek Gite

The Debian Linux 12 backports repository offers updated versions of software packages for Debian Stable releases. These packages are sourced from Testing (and sometimes Unstable) branches of Debian, and then optimized and recompiled to function on the current Stable release, such as Bookworm. Let us see how to install and use Debian Linux 12 "Bookworm" Backports repository. Love this? sudo share_on: Twitter - Facebook - LinkedIn - Whatsapp - Reddit The post How to enable Debian 12 Backports repository appeared first on nixCraft. 2024-05-11T11:02:39Z 2024-05-11T11:02:39Z Vivek Gite

I need to copy or clone file ownership and permissions from another file on Linux. Is there a bash command line option to clone the user, group ownership and permissions on a file from another file on Linux operating system? Love this? sudo share_on: Twitter - Facebook - LinkedIn - Whatsapp - Reddit The post How to copy permissions from one file to another on Linux appeared first on nixCraft. 2024-05-08T22:06:06Z 2024-05-08T22:06:06Z Vivek Gite

If you are writing a Bash shell script, you should read command-line arguments into an array for some time. This allows us to process any number of arguments provided when the script is run. This makes the script adaptable to different use cases. Instead of dealing with fixed variables like $1, $2, $3, etc., you can work with any number of arguments more dynamically using bash for loop or bash while loop, depending upon your needs. Arrays make it simple to loop through each argument and perform operations on them, whether basic printing or complex processing. Bash provides a mapfile (readarray command) internal built-in command to read lines from a file into an array variable. Let us see how to use mapfile to read all command line arguments into an array. Love this? sudo share_on: Twitter - Facebook - LinkedIn - Whatsapp - Reddit The post A Bash Script to Read All Command Line Arguments into an Array: Simplify Argument Handling appeared first on nixCraft. 2024-05-07T10:40:08Z 2024-05-07T10:40:08Z Vivek Gite

CentOS, RHEL (Red Hat Enterprise Linux), Fedora and other clones of RHEL, such as Oracle, Alma, and Rocky, offer support for version pinning. This feature allows developers and system administrators to lock a particular package to a specific version, preventing it from being automatically updated by yum or dnf commands. Sometimes, it is necessary to protect packages from being updated to newer versions to avoid incompatibility issues with your applications. For example, you can lock down PHP version 8.3.6 and avoid using updated PHP version 8.4. Let us see how to lock a package to a specific version, only exclude a package from yum update or dnf update on a CentOS, RHEL, Fedora, and friends. Love this? sudo share_on: Twitter - Facebook - LinkedIn - Whatsapp - Reddit The post How to Pin Versions in Yum or Dnf for RHEL or CentOS Linux appeared first on nixCraft. 2024-05-07T09:01:47Z 2024-05-07T09:01:47Z Vivek Gite

Here's a quick tip for vim users. You can perform find and replace operations within a visual selection in Vim for text or code block. Visual selection for finding and replacing text in Vim allows developers and Linux/Unix users precise and efficient text editing. It's handy when you want to change specific portions of text or code blocks within a larger file without affecting other occurrences. This method required to minimizing manual search and reducing the risk of unintended code or text modifications. Let us see how to find and replace in Vim visual mode selection. Love this? sudo share_on: Twitter - Facebook - LinkedIn - Whatsapp - Reddit The post How to perform find and replace operations within a visual selection in Vim appeared first on nixCraft. 2024-05-07T06:14:33Z 2024-05-07T06:14:33Z Vivek Gite

Unhide is a little handy forensic tool to find hidden processes and TCP/UDP ports by rootkits / LKMs or by another hidden technique. This tool works under Linux, Unix-like system, and MS-Windows operating systems. Love this? sudo share_on: Twitter - Facebook - LinkedIn - Whatsapp - Reddit The post How to find hidden processes and ports on Linux/Unix/Windows appeared first on nixCraft. 2024-05-07T05:05:51Z 2024-05-07T05:05:51Z Vivek Gite

Bash is a command language interpreter compatible with sh. It can execute commands read from a file or keyboard. On Debian Linux, bash-completion is a set of shell functions that uses Bash's programmable completion feature. This page provides instructions on installing and enabling Bash auto-completion on Debian Linux versions 10, 11, and 12 to increase productivity by writing custom bash code. Love this? sudo share_on: Twitter - Facebook - LinkedIn - Whatsapp - Reddit The post How to add bash auto completion in Debian Linux appeared first on nixCraft. 2024-05-06T15:51:25Z 2024-05-06T15:51:25Z Vivek Gite

Recently, I had a learning experience with cron jobs and acme.sh. acme.sh is an excellent tool that simplifies the management of Let's Encrypt TLS (SSL) certificates. It makes obtaining and renewing these essential security certificates for your web server easier. Recently, I moved my server from Linode to AWS, which was a new environment for me. Initially, everything appeared to be working correctly, and I assumed everything was running smoothly. However, I forgot to migrate the cron job that acme.sh uses to renew the certificate automatically. This oversight caused my Let's Encrypt certificates to expire, resulting in security warnings and potential disruptions for visitors to my website. Opps! Love this? sudo share_on: Twitter - Facebook - LinkedIn - Whatsapp - Reddit The post How to add cron job entry for acme.sh appeared first on nixCraft. 2024-05-03T06:43:12Z 2024-05-03T06:43:12Z Vivek Gite

{nixCraft Patreon supporters content}Below is a sneak peek of this content! Ubuntu 24.04 LTS (Noble Numbat) was launched on April 25th, 2024. This new version will be supported for five years until June 2029. The armhf architecture now provides support for the Year 2038 problem. The upgrades include significant updates to core packages like Linux kernel, systemd, Netplan, […]The post How to Upgrade Ubuntu 22.04 to 24.04 LTS: A Complete Guide appeared first on Opensource Flare✨. 2024-04-26T18:25:08Z 2024-04-26T18:25:08Z Vivek Gite

Ubuntu 24.04 LTS (Noble Numbat) was launched on April 25th, 2024. This new version will be supported for five years until June 2029. The armhf architecture now provides support for the Year 2038 problem. The upgrades include significant updates to core packages like Linux kernel, systemd, Netplan, toolchain upgrades for better development support, enhanced security measures, and performance optimizations. It also has an updated GNOME desktop environment and other default applications. Let us see how to upgrade Ubuntu 22.04 LTS to Ubuntu 24.04 LTS using the CLI over ssh-based session. Love this? sudo share_on: Twitter - Facebook - LinkedIn - Whatsapp - Reddit The post How to Upgrade Ubuntu 22.04 to 24.04 LTS: A Complete Guide appeared first on nixCraft. 2024-04-26T08:33:21Z 2024-04-26T08:33:21Z Vivek Gite

AWS SES (Amazon Simple Email Service) is a cloud-based email-sending service that is both reliable and cost-effective. This service is offered by Amazon Web Services. Postfix is a popular email server for Debian and Unix-like systems. It is an open-source Mail Transfer Agent (MTA) responsible for routing and delivering emails. Debian Linux is a widely used Linux distribution known for its stability and user-friendliness for server usage. Let us see how to integrate AWS SES with the Postfix MTA on Debian Linux version 11/12. Love this? sudo share_on: Twitter - Facebook - LinkedIn - Whatsapp - Reddit The post How to configure AWS SES with Postfix MTA on Debian Linux appeared first on nixCraft. 2024-04-19T07:04:06Z 2024-04-19T07:04:06Z Vivek Gite

When you run the sudo apt update, you may see the following message or error on a Debian Linux: Err:5 http://deb.debian.org/debian buster-backports Release 404 Not Found [IP: 146.75.34.132 80] Reading package lists... Done E: The repository 'http://deb.debian.org/debian buster-backports Release' no longer has a Release file. N: Updating from such a repository can't be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details. Here is how to fix this issue. Love this? sudo share_on: Twitter - Facebook - LinkedIn - Whatsapp - Reddit The post The repository ‘http://deb.debian.org/debian buster-backports Release’ no longer has a Release file. appeared first on nixCraft. 2024-04-14T20:42:01Z 2024-04-14T20:42:01Z Vivek Gite

You can find the timezone in Linux using the command line. The easiest way to do this is to type the "timedatectl" command and look for the "timezone" line when using modern Linux distros with systemd. There are other commands and ways to temporarily switch to a new timezone for date calculations. Love this? sudo share_on: Twitter - Facebook - LinkedIn - Whatsapp - Reddit The post How do I find out my timezone in Linux? appeared first on nixCraft. 2024-04-06T01:06:44Z 2024-04-06T01:06:44Z Vivek Gite