Ubuntu Linux

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In Debian and Ubuntu Linux, an “rc” status package means the package has been uninstalled, but its configuration files remain on the disk and take up space. Sometimes, certain directories are also in the /var/ directory. When you type the sudo apt remove pkg1 command, it deletes most of the data, but config files are left alone in case you reinstall that package again. You can free up disk space by removing unwanted config files.
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How do I capture a specific protocol or port, such as 80 (HTTP) or 443 (HTTPS), using the TCPDump tool under Linux/UNIX? How do I record traffic with TCPDump and find problems later on with my network or server issues? Let’s dive into the nitty-gritty of capturing and analyzing your network traffic for trapshooting network and server issues.
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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.
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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.
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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.
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See all Ubuntu Linux related FAQ
The Uncomplicated Firewall (UFW) needs to be configured to allow traffic on UDP ports 67 and 68, regardless of whether the Dynamic Host Configuration Protocol (DHCP) server is local or remote. Additionally, it may be necessary to open both TCP and UDP port 53, which are used for Domain Name Service (DNS). In small business and home environments, typically, both DNS and DHCP services come from a single device. Hence, it would be best if you opened both DHCP and DNS ports using the ufw command.
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