Fresh Ubuntu Server install can reach the internet but not resolve local hostnames
I installed a brand-new Ubuntu Server 26.04.1 machine using a simple DHCP setup. The local DHCP and DNS services run on the same older server, and internet DNS…
DHCP
Windows and Router Show Different IPv4 Addresses for the Same Device
I'm troubleshooting an inconsistent IPv4/DHCP problem on a Windows 11 PC connected to a FRITZ!Box 7530 AX. Windows Settings sometimes shows no IPv4 address, while ipconfig reports 192.168.178.128…
How can you verify that no clients still depend on an old DNS resolver?
Changing DHCP options and static settings does not guarantee that every client has moved to the new DNS service. Appliances, containers, VPN profiles, hard-coded application settings, and systems…
How can you verify that no clients still use an old DNS resolver?
Changing DHCP options and static configurations does not prove that every client has migrated. Appliances, containers, VPN profiles, hard-coded application settings, and rarely booted systems may continue querying…
IPv4 fails only on my laptop’s condo Wi-Fi while IPv6 still works
My Windows laptop has a very specific connectivity problem: IPv4 stops working when I connect to my condominium's Wi-Fi, while IPv6 continues to work. The same laptop has…
Why is my DHCP server assigning the same IP to different BMC interfaces?
I set up a small Windows 10 Pro system running Tiny PXE to provide DHCP and PXE services on a dedicated 192.168.26.x network for installing and testing servers…
Ethernet Connection Has No Valid IP Configuration or DHCP Server
After my provider made changes to the service, the Wi-Fi network was reset. Most devices reconnected normally, and one of my Ethernet-connected PCs works without any issues. However,…
Windows Wi‑Fi connects but cannot obtain an IPv4 address
My Acer Nitro V 15 connects to Wi‑Fi, but Windows reports no internet access. The wireless adapter receives a 169.254.x.x address instead of a normal IPv4 address from…
Physical Devices Can't Get DHCP Leases from a Hyper-V VM
I have a Windows 11 Enterprise LTSC host running Hyper-V with an external virtual switch. The VM provides DHCP, DNS, and WDS services. Other VMs connected to the…
Do all servers still need manually configured static IP addresses?
I was raised with the rule that servers should always use static IP addresses. That still seems obviously necessary for foundational services such as domain controllers, DNS, DHCP,…
Microphone Not Working and Ethernet DHCP Issues on Linux Mint
I'm using a Lenovo LOQ 15 with Linux Mint Cinnamon. My Sennheiser HD569 microphone works normally in Windows 11, but in Linux it doesn't pick up my voice…
How can I connect two libvirt VMs on an isolated network?
I'm building a small lab with two Debian Trixie VMs: one will act as a router and DHCP server, while the other should obtain a DHCP lease from…
Why can’t my libvirt VMs communicate on an isolated network?
I'm building a small lab with two Debian Trixie VMs: one will act as a router and DHCP server, while the other should obtain a lease from it…
Desktop Connects to Home Wi‑Fi but Keeps Losing Internet Access
My desktop connects to our home Wi‑Fi, but Windows usually reports that there's no internet. Every other device in the house works normally, and this PC can connect…
How would you discover assets across 50+ undocumented sites?
I've inherited an environment spanning more than 50 LANs and sites with very little trustworthy documentation. I need to build an inventory of PCs, laptops, servers, switches, firewalls,…
Should I Learn Networking Before Windows Server Administration?
I'm preparing for a career in system administration and want to build a solid foundation. Would learning networking fundamentals first—such as IP addressing and subnetting, DNS and DHCP,…
What’s the Best Way to Build and Maintain an Accurate IP Inventory?
I've documented my Proxmox cluster, switch connections, DHCP configuration, DNS zones, forwarding, and related network details. The remaining task is documenting every IP address, but I keep finding…
Should I Learn Networking Before Windows Server Administration?
I'm preparing for a system administration career and want to build a solid learning plan. Would studying networking fundamentals first—such as IP addressing and subnetting, DNS and DHCP,…
Ethernet Shows “Unidentified Network” While Wi‑Fi Works
I recently moved into a new home and set up internet service with Bell MTS. The Wi‑Fi works normally, but connecting my computer by Ethernet only gives me…
What’s the Best Way to Build an Accurate IP Inventory?
I've documented my Proxmox cluster, switch connections, inter-switch links, DHCP configuration, DNS zones, and forwarding rules. The remaining task is documenting every IP address on the network, but…