What is Firewalld? It is a front-end management tool for the Linux kernel’s Netfilter/iptables system. It provides a more user-friendly interface for managing firewall rules, simplifying the complexity of directly using iptables. Firewalld supports dynamic updates, allowing modifications to rules without restarting the service, and introduces the concepts of “zones” and “services” for quickly switching … Read more
Basic Concepts of Firewalls All security topics are inseparable from the involvement of firewalls, especially in <span>OpenWrt</span>. Understanding the concept of firewall zones and the three types of rules is essential for correctly configuring SSH, VPN, port forwarding, and other functions. What is a Firewall Zone? In OpenWrt, firewalls do not write rules for individual … Read more
Essential Guide to Deploying Linux Firewall: From Basic Protection to Advanced Rules, Easy for Beginners ** Hello everyone! Previously, when sharing about Linux SSH remote management, some friends in the background commented: “Remote connection is convenient, but the server is exposed to the network, and I am always worried about being attacked. How can I … Read more
Completed Content I will create a simple firewall demo to help you familiarize yourself with network kernel programming. This demo will be implemented based on the Linux Netfilter framework. Basic Framework Basic Concepts Netfilter Framework Netfilter is a framework in the Linux kernel used for filtering, modifying, and redirecting network packets. It provides multiple hook … Read more
【Hillstone InsightsASIC】•Article 7 Are you as steady as a mountain in the face of the “Elephant Flow” of data? In the wave of digitalization, a flood of data sweeps across various industries. Among this traffic, there is a particularly special type known as“Elephant Flow”— those long-lasting, massive single data streams. They are not light “cars,” … Read more
Common Linux Commands – Part 5 5. iptables Firewall: Four Tables and Five Chains: The default four rule tables: raw table: Determines whether to track the state of the packet, includes rule chains OUTPUT, PREROUTING mangle table: Modifies packet content, used for traffic shaping, sets packet marks, includes rule chains INPUT, OUTPUT, FORWARD, PREROUTING, POSTROUTING … Read more
Common Linux Commands – Part 6 6. Application Commands: -t filter: Indicates adding rules at the end of the chain (if no table name is specified, the default is the filter table) -I INPUT: Indicates adding an inbound rule at the first line of the filter table (-I INPUT 2 indicates adding an inbound rule … Read more
Cisco Certification | Huawei Certification | IT Technology | Network Engineer👇3000-person technical exchange QQ group Note: [Public Account] Faster access When we enjoy the convenience brought by the internet, few people think of the behind-the-scenes heroes that make everything possible. Today, we will unveil one of these mysterious roles—ports. Ports play a crucial role in … Read more
Click the blue text above to follow us. By configuring NAT and policy routing functions, campus network users can access the Internet in different ways. Networking Requirements Student users at a certain school can access the Internet through the education network, while teacher users can access the Internet directly. The IP address allocated to the … Read more
To implement the “2024 Work Plan for Deepening the Large-Scale Deployment and Application of IPv6” issued by the Central Cyberspace Affairs Commission, the National Development and Reform Commission, and the Ministry of Industry and Information Technology, and to promote the early activation of IPv6 for internet access in various levels of party and government organs, … Read more