A Simple Introduction to Web Sockets The WebSocket API is an advanced technology that makes it possible to open a two-way interactive communication session between the user's browser and a server. With this API, you can send messages to a server and receive event-driven responses without having to poll the server for a reply. Networking
DHCP Basics Dynamic Host Configuration Protocol (DHCP) is a standard protocol that allows a server to dynamically distribute IP addressing and configuration information to clients. In the Classless Inter Domain Routing (CIDR) environment of IPv4 the following parameters should be defined on every IPv4 host:: 1. ip addres, 2. subnet mask, 3. default gateway Networking
Understanding DHCP Relay Agents DHCP relay agent is a small program that relays DHCP/BOOTP messages between clients and servers on different subnets. DHCP/BOOTP relay agents are part of the DHCP and BOOTP standards and function according to the Request for Comments (RFCs), standard documents that describe protocol design and related behavior. Networking
rsyslog on debian server Enable Rsyslog Logging on Debian This step by step tutorial will take you through how to enable rsyslog logging on Debian 12. Debian 12 bookworm uses systemd-journald logging by default. As such, it has deprecated the use of Rsyslog for logging so as to prevent the log messages being written twice on disk. So, how can you enable rsyslog logging on Debian 12 and higher? Rsyslog vs Journald Rsyslog and Systemd-journald are both logging systems commonly used in Linux distributions for collecting and storing log data. Debian
Illustrated introduction to Linux iptables Gee, it's my turn to throw some light on iptables! There are hundreds or even thousands of articles on the topic out there, including introductory ones. I'm not going to put either formal definitions here nor long lists of useful commands. I would rather try to use layman's terms and scribbling as much as possible to give you some insights about the domain before going to all these tables, rules, targets, and policies. Networking
A Visual Guide to SSH Tunnels: Local and Remote Port Forwarding SSH is yet another example of an ancient technology that is still in wide use today. One of my favorite parts of this technology is SSH Tunnels... Networking
Bridge vs. Switch The difference between these two networking devices has been an unsolvable mystery to me for quite some time. For a while, I used to use the words 'bridge' and 'switch' interchangeably. But after getting more into networking, I started noticing that some people tend to see them as rather different devices... So, maybe I've been totally wrong? Maybe saying 'bridge aka switch' is way too inaccurate? Networking
Computer Networking Introduction: Ethernet and IP This article is my layman's attempt to sort the basic things out with the minimum words and maximum drawings. The primary focus will be on the Data link layer (OSI L2) of wired networks where the Ethernet is the king nowadays. But I'll slightly touch upon its neighboring layers too. Networking
BIND: Disabling IPv6 responses in bind dns server When using Bind9 as DNS service in your own network, it can be helpful to disable IPv6 (AAAA) responses to avoid the client to try to communicate via IPv6 if it hasn't been setup. Debian Linux Networking
BIND DNS server - permission denied How Fix BIND DNS server permission denied problem after log directory or log file change. Bind server failed with error: isc_stdio_open failed: permission denied Debian Linux Networking
Bonding - teaming 802.3ad LACP on Debian Server NIC teaming (Ling Aggregation) presents an interesting solution to redundancy and high availability in the server/workstation computing realms. With the ability to have multiple network interface cards, an administrator can become creative in how a particular server accessed or create a larger pipe for traffic to flow through to the particular server. Debian Linux Networking
Debian - Source Routing In some circumstances we want to route packets differently depending not only on ip destination addresses, but also on other packet fields: source address, IP protocol, transport protocol ports, or even packet payload. This task is called policy based routing - PBR. Debian Linux Networking
