Score:0

Ubuntu

How to fix a broken port: *:x11

Run

10/22/22, 8:50 AM

I am trying to figure out what are running on my ports:

Port 4000:

$ lsof -i :4000
COMMAND    PID     USER   FD   TYPE  DEVICE SIZE/OFF NODE NAME
apache2 129245     root    6u  IPv6  999421      0t0  TCP *:4000 (LISTEN)
apache2 129246 www-data    6u  IPv6  999421      0t0  TCP *:4000 (LISTEN)
apache2 129246 www-data   22u  IPv6 1000516      0t0  TCP static.164.77.12.49.clients.your-server.de:4000->178-164-233-141.pool.digikabel.hu:47972 (ESTABLISHED)
apache2 129247 www-data    6u  IPv6  999421      0t0  TCP *:4000 (LISTEN)
apache2 129248 www-data    6u  IPv6  999421      0t0  TCP *:4000 (LISTEN)
apache2 129249 www-data    6u  IPv6  999421      0t0  TCP *:4000 (LISTEN)
apache2 129250 www-data    6u  IPv6  999421      0t0  TCP *:4000 (LISTEN)
apache2 129254 www-data    6u  IPv6  999421      0t0  TCP *:4000 (LISTEN)

That seems ok to me. But on my port 6000:

$ lsof -i :6000
COMMAND    PID     USER   FD   TYPE  DEVICE SIZE/OFF NODE NAME
apache2 129245     root   10u  IPv6 1000453      0t0  TCP *:x11 (LISTEN)
apache2 129246 www-data   10u  IPv6 1000453      0t0  TCP *:x11 (LISTEN)
apache2 129247 www-data   10u  IPv6 1000453      0t0  TCP *:x11 (LISTEN)
apache2 129248 www-data   10u  IPv6 1000453      0t0  TCP *:x11 (LISTEN)
apache2 129249 www-data   10u  IPv6 1000453      0t0  TCP *:x11 (LISTEN)
apache2 129250 www-data   10u  IPv6 1000453      0t0  TCP *:x11 (LISTEN)
apache2 129254 www-data   10u  IPv6 1000453      0t0  TCP *:x11 (LISTEN)

It looks quite different from port 4000.

What is TCP *:x11?

I get This site can’t be reached when accessing it on my browsers.

How can I fix it?

1 + 5

apache2

lsof

muru

10/22/22, 8:52 AM

What does `grep 6000 /etc/services` say?

Run

10/22/22, 9:02 AM

@muru `x11 6000/tcp x11-0 # X Window System` - dunno what it is

muru

10/22/22, 9:26 AM

`/etc/services` is the file that contains names for the various ports (e.g., "ssh" for port 22, "http" for port 80, etc.) for tools like `lsof`, `netstat`, etc. In this case, "x11" is the name given to port 6000, so you see `:x11` instead of `:6000`. It's only for presentation - you can't access `:x11` on your browser. Now, is your "This site can’t be reached" error from trying to access `:x11`?

Run

10/24/22, 10:07 AM

@muru "This site can’t be reached" is from :6000

muru

10/24/22, 11:18 AM

Just `:6000`? No IP?

Score:1

Ubuntu

HuHa

10/22/22, 9:36 AM

Of course you can't do anything with your web browser on that X11 port: That port speaks X protocol, not http, https or ftp which is what your web browser understands.

What do you expect to happen when you connect your browser there?

0 + 6

Run

10/24/22, 10:03 AM

I am just trying to run a WordPress site on that port. Other ports are ok. Not this. Why??

HuHa

10/24/22, 10:14 AM

Because that's a predefined "well-known" port number. You _can_ repurpose such port numbers, but that is asking for trouble; you are breaking compatibility for all kinds of things. I'd strongly advise against that.

HuHa

10/24/22, 11:03 AM

See also `/etc/services` and https://en.wikipedia.org/wiki/List_of_TCP_and_UDP_port_numbers and https://www.sciencedirect.com/topics/computer-science/registered-port

Run

10/28/22, 10:42 AM

I think that port is taken up by X Window System - X11. Dunno what it is. Never installed it. It just crept in I guess. https://en.wikipedia.org/wiki/X_Window_System

HuHa

10/28/22, 10:56 AM

It didn't "creep in", they registered that port 30+ years ago for X11. That's what that `/etc/services` file is there for.

Run

10/30/22, 9:35 PM

Aw I see. Thank you!

Elon Musk

I sit in a Tesla and translated this thread with Ai:

EN: How to fix a broken port: *:x11

TH: วิธีแก้ไขพอร์ตที่เสีย: *:x11

RO: Cum să remediați un port rupt: *:x11

RU: Как исправить неработающий порт: *:x11

VI: Cách khắc phục cổng bị hỏng: *:x11

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