https://devopstales.github.io/tags/sdn/ Recent content in SDN on DevOpsTales Hugo -- gohugo.io en-US Mon, 21 Sep 2026 00:00:00 +0000 https://devopstales.github.io/virtualization/proxmox-sdn-missing-source-directive/ Mon, 21 Sep 2026 00:00:00 +0000 https://devopstales.github.io/virtualization/proxmox-sdn-missing-source-directive/ If you have ever applied a Proxmox VE Software-Defined Network configuration and seen this warning pop up in the task view, you are not alone: WARN: missing 'source /etc/network/interfaces.d/sdn' directive for SDN support! Created symlink /etc/systemd/system/multi-user.target.wants/dnsmasq@testzone.service -> /lib/systemd/system/dnsmasq@.service. TASK WARNINGS: 1 It looks harmless, and in most cases it is. But if you want SDN-generated networks to actually come up on the node, that one line is the difference between a pending configuration and a running one. This post explains where the warning comes from in the Proxmox source code, why the fix is a single source directive, and how to verify the whole pipeline works afterwards.