# Ports "in use" permanently, even after reboot **URL:** \ **Category:** Rocky Linux Help & Support\ **Created:** [August 8, 2023, 11:00pm UTC](https://forums.rockylinux.org/t/ports-in-use-permanently-even-after-reboot/10974 "2023-08-08T23:00:59Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![M-Pixel](https://avatars.discourse-cdn.com/v4/letter/m/e8c25b/32.png) [@M-Pixel](https://forums.rockylinux.org/u/M-Pixel)\ **Post date:** [August 8, 2023, 11:00pm UTC](https://forums.rockylinux.org/t/ports-in-use-permanently-even-after-reboot/10974/1 "2023-08-08T23:00:59Z")
I have a pretty strange issue on Rocky 9.2. I’ve scoured Stack Overflow and elsewhere, and haven’t found anything that gives me any usable insight or results. Got a Node.JS Express app which listens on a few ports - both HTTP, HTTPS, and WebSocket. Trying to restart it, I got `"Error: listen EADDRINUSE: address already in use 0.0.0.0:8000"`. It’s reproducible: If I then run the process specifying port 8001, it works. CTRL + C, re-run with port 8001 again: error. Re-run with port 8002: works the first time, error the second time. Here’s what I’ve observed: - This only happens when I specify `0.0.0.0:8000`. When I specify `8000` only, it binds only to IPv6, and re-starts without any issues. - At first I thought it was an issue with Podman, but then found that it occurs when running the process directly on the host. - `netstat -na` doesn’t output any lines with the afflicted ports (including w/ sudo). - `lsof` doesn’t output any lines with the afflicted ports (including w/ sudo). - `ss` doesn’t output any lines with the afflicted ports (including w/ sudo) - `sudo sysctl -w net.ipv4.tcp_fin_timeout=1` + `sudo sysctl -w net.ipv4.tcp_tw_reuse=1` doesn’t solve the issue - The really perplexing part: **rebooting doesn’t free up the ports**. Where is this state being stored? How can I probe the kernel to figure out what’s going on under the hood to cause this issue? Running the same software on an Ubuntu server, I don’t get this issue. ---
**Author:** ![M-Pixel](https://avatars.discourse-cdn.com/v4/letter/m/e8c25b/32.png) [@M-Pixel](https://forums.rockylinux.org/u/M-Pixel)\ **Post date:** [August 9, 2023, 2:14am UTC](https://forums.rockylinux.org/t/ports-in-use-permanently-even-after-reboot/10974/2 "2023-08-09T02:14:34Z")
Well, I ended up figuring out the solution… ```auto [mpixel@server NodeApp]$ ls -la total 140 drwxr-xr-x. 11 mpixel mpixel 4096 Aug 8 18:58 . drwxr-xr-x. 6 mpixel mpixel 181 Aug 1 13:28 .. srwxr-xr-x. 1 root root 0 Aug 8 12:50 0.0.0.0:443 srwxr-xr-x. 1 root root 0 Aug 8 12:50 0.0.0.0:80 srwxr-xr-x. 1 mpixel mpixel 0 Aug 8 14:05 0.0.0.0:8000 srwxr-xr-x. 1 mpixel mpixel 0 Aug 8 14:23 0.0.0.0:8001 srwxr-xr-x. 1 mpixel mpixel 0 Aug 8 14:38 0.0.0.0:8002 srwxr-xr-x. 1 mpixel mpixel 0 Aug 8 14:05 0.0.0.0:8443 srwxr-xr-x. 1 mpixel mpixel 0 Aug 8 14:23 0.0.0.0:8444 srwxr-xr-x. 1 mpixel mpixel 0 Aug 8 14:38 0.0.0.0:8445 srwxr-xr-x. 1 mpixel mpixel 0 Aug 8 14:56 0.0.0.0:9000 srwxr-xr-x. 1 mpixel mpixel 0 Aug 8 14:56 0.0.0.0:9001 srwxr-xr-x. 1 mpixel mpixel 0 Aug 8 15:42 0.0.0.0:9002 srwxr-xr-x. 1 mpixel mpixel 0 Aug 8 15:42 0.0.0.0:9003 srwxr-xr-x. 1 mpixel mpixel 0 Aug 8 16:05 192.168.23.77:8000 srwxr-xr-x. 1 mpixel mpixel 0 Aug 8 16:05 192.168.23.77:8443 srwxr-xr-x. 1 mpixel mpixel 0 Aug 8 16:46 '*:443' srwxr-xr-x. 1 mpixel mpixel 0 Aug 8 16:46 '*:80' ... ``` Evidently, when given “0.0.0.0:####” as a port, Express / NodeJS will create a Unix socket on the filesystem, relative to the current working directory, and doesn’t clean it up. These can be simply removed with `rm`.