LW IT Solutions
19 articles in this category
Follow this category by RSSWhen a connection fails, the cause is often somewhere unexpected. In this section I break networking topics into manageable pieces, from a DNS record to a firewall rule.
You will find guides and explanations covering VLANs, routing, Wi-Fi, firewalls, self-hosting and monitoring. I also look at how the pieces connect: how devices communicate, which connection is blocked and how to spot the cause.
Security headers are checked by their names far too often. The name says a rule exists; only the value says whether it does anything – and some values cancel the very rule they belong to.
SPF checks which server sent the message. DKIM checks whether the message was altered. Neither of them rejects anything – that is what DMARC does, and most domains never switch it on.
A failover restores the line and ends every connection that was using it. The switch is not a hiccup in an ongoing session – it is the end of that session and the start of a different one.
Fifteen devices drawing 168 watts can exhaust a 400-watt switch, because a switch reserves by class rather than by measurement. Which of the two numbers applies is a setting – and knowing which one decides whether the sixteenth device gets power.
Six labels on a container, one name that has to match in three of them, and a bcrypt hash that Docker Compose quietly takes apart. None of the three mistakes produces an error message.
A technical guide on setting up a sovereign Zero-Trust DNS infrastructure using Pi-hole and Unbound with DNSSEC validation and query minimization.
UniFi ZBF requirements and a practical review of return traffic, gateway services and routed traffic within the same zone.
A technical step-by-step guide on deploying IEEE 802.1X RADIUS authentication and dynamic VLAN assignment on Ubiquiti UniFi switches for enterprise LAN security.
A technical analysis of why modern surveillance deployments require Cat6 PoE cabling over legacy coax, combined with strict VLAN segmentation and WAN OUT drop rules for complete local UNVR/UNAS isolation.
Technical guide on reading solar inverter registers locally via Modbus TCP/RTU and automating load shedding with DIN-rail contactors during grid failures.
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