https://i.redd.it/5azvg5qhgcph1.gif Every time a port was taken I ended up running ss, then digging in /proc, then checking nftables, then docker inspect. Made a tool that just prints it. portclue → table of all listening ports with process, bind scope, docker or host portclue 5900 → who owns it, loopback-only or all interfaces, and whether your firewall rules allow it portclue --json → pipe into jq Works without ss or lsof installed (reads netlink and /proc directly). Read-only, Linux TCP listeners only, no UDP. Install: curl -fsSL https://raw.githubusercontent.com/pbxqdown/portclue/v0.1.2/scripts/install.sh | sh https://github.com/pbxqdown/portclue Hope it saves someone the twenty minutes I wasted on this.   submitted by   /u/Fair_Refuse_5998 [link]   [comments]