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geekinthesticks

Member

From: England

Registered: 2011-09-21

Posts: 143

Website

Can't Connect Externally to Port 6546.

I have two mythtv frontends and I want to use the remote control protocol on port 6546. On myth3.bantercat.co.uk I can connect to port 6546 both from the computer itself and from another computer on the network using netcat:

scamper2 ~ » netcat myth3.bantercat.co.uk 6546
MythFrontend Network Control
Type 'help' for usage information
---------------------------------
# exit

However, on myth2.bantercat.co.uk I can only connect internally and not from another computer on the network. I do run a firewall (Shorewall), but it does not block any internal traffic and as I can connect to one box from an external computer, I don't think this is the problem. So how can I work out what is stopping me from being able to connect to myth2 from another computer on the same network?

darrenldl

Member

Registered: 2013-06-04

Posts: 31

Re: Can't Connect Externally to Port 6546.

Hello,

I did 30 minutes of reading on MythTV and still don't feel like I fully understand it, so I am giving a blind shot here, sorry if I'm not helpful at all.
There are a few assumptions I made below, correct me if they are wrong.

So, within a network, you have two front ends, one being myth3.bantercat.co.uk, the other being myth2.bantercat.co.uk.
By

On myth3.bantercat.co.uk I can connect to port 6546 both from the computer itself and from another computer on the network

you mean you can connect to port 6546 from the myth3.bantercat.co.uk computer itself, and from another computer on the same network to myth3.bantercat.co.uk as well.

By

However, on myth2.bantercat.co.uk I can only connect internally and not from another computer on the network.

you mean you can connect to port 6546 from the myth2.bantercat.co.uk computer itself, but, you cannot connect from another computer on the same network to myth2.bantercat.co.uk.

Your firewall does seem not to be blocking the traffic, as you've mentioned, a computer from another network can reach it.

You can try installing nmap(which is in the official repository), then do a port probe(scan) to myth2.bantercat.co.uk, to check if the port is reachable by the other computer on the same network.
WARNING : If those are your equipments and you are in a local network, port scanning should be fine as long as you don't intefere with other people's things, OTHERWISE YOU MAY HAVE LEGAL ISSUES. Certain ISPs, especially in UK, explicitly disallow port scaning, so make sure you don't port scan equipments outside your own network as well.

 nmap -p 6546 myth2.bantercat.co.uk 

The output should look similar to this( which I am probing port 80 of my router, 192.168.1.1 )

Nmap scan report for 192.168.1.1
Host is up (0.0029s latency).
PORT   STATE SERVICE
80/tcp open  http

If everything's functioning properly, the STATE should be open for port 6546.
If it's open, then it should be your other computer's problem(program version mismatch perhaps?) or firewall problem(which seems unlikely).

Good luck!

Last edited by darrenldl (2013-11-20 17:08:15)