Netcat is built into most if not all Linux distributions. It is an incredibly useful tool for quick network tests: to see if a device is reachable or a service is running. Seeing a “Connection refused” in netcat is in itself already valuable information as it could indicate that the remote host is reachable, but the service just isn’t running.
Continue readingPage 2 of 2
As a first simple tool I’ve put up a basic IPv4 subnet calculator. It’s fully clientside and accepts the common input methods (1.2.3.4/32 or 1.2.3.4/255.255.255.255). An IPv6 one is also in the works.
When setting up Apache from scratch on a new server, and you create a new DocumentRoot for a new VirtualHost, you’ll often find yourself running into:
ForbiddenContinue reading
You don't have permission to access / on this server.
When troubleshooting an issue on any device where network connectivity is impacted, a packet capture is still king. This is not to say every 403 Forbidden error needs to be examined in Wireshark, but when a user reports their browsing saying the connection was reset or a timeout was hit, it might be time to fire up tcpdump.
Continue reading