Picture this: Monday morning, the office fills up — and nobody can get on the network. Laptops are pulling addresses from the 192.168.100.x range, even though you’ve had 10.0.0.x configured for years. The default gateway leads nowhere. No internet. People are furious. The CEO is already blowing up your phone. You stare at the console […]
DHCP Snooping — What It Is and How to Protect Your Network from a Rogue Читать дальше
You’re sitting in front of someone else’s machine. No admin rights. Can’t install anything. The network is acting up and you need answers right now. Sound familiar? Whether you’re a sysadmin doing a quick on-site visit, a support tech walking a user through troubleshooting, or a developer who just needs to know if port 443
NetDiag: Free Portable Network Diagnostic Tool for Windows Читать дальше
You walk in Monday morning. Coffee in hand. Users are already in the ticket queue screaming: «Internet is down», «My PC got a weird IP address», «The gateway is 192.168.0.1 instead of our 10.10.0.1». Congratulations — you have a rogue DHCP server on your network. It could be an employee’s home router plugged into the
DHCPScan – A utility for finding Rogue DHCP Читать дальше
After years in the field, I’ve figured out one universal truth: users come to you with a problem, you fix DNS, they leave happy. Classic. So today we’re going deep on DNS in Linux — from the basics all the way down, with practical tricks, real cases from the trenches, and just enough dark humor
How DNS Works in Linux: Brief, to the Point, and Practical Читать дальше
