Opening ports on router

ChrisH

ChrisH

Suspended / Banned
Messages
4,146
Name
Chris
Edit My Images
Yes
I've spent hours and hours trying to figure why I can't get any ports to open on a Netgear R6400 router.

I say say no ports but I've got a permanently open port that I use for my CCTV system. It's open whether in the routing table or not.

I'm trying to open an extra port for a 3d printer controller.

Although I put the IP and port number in the routing table and it saves it, it would appear using a port scanner that the port never opens. I'm pulling what little hair I have out.

I'm on Virgin cable, but I don't think that matters. If I select remote access to the router it opens that port immediately and deselecting it closes the port.

Any suggestions would be welcome, I've been a computer engineer for years but this has me stumped.

Maybe just a crap router design or something I'm missing.
 
Presumably an inbound port for accessing the printer remotely?

Depends on the version of the hub but should just set up a new service for the port(s) you want then set up a forward to the local IP.

Remote access is just allowing external access to the router admin iirc.

Best to give your printer a static local IP so the port forward doesn't stop working when the dhcp lease expires. Also presumably you use a dynamic dns service so the same thing doesn't happen when your isp lease expires.
 
I need a port open to monitor a raspberry pi based 3d printer server. I've given it a fixed IP of 192.168.1.21 and assigned port 810 in the port forwarding table. It never opens port 810 so if I then try an connect with 81.xx.xx.xx:801 it won't let me in.

I've used a port scanner and it says the port is closed. If however I scan the port my Router is set up for my cctv, a similar port It shows as open on a port scanner.

BAFFLED.COM
 
neil_g said:
Which hub do you have?

Presumably the pi will respond on that port?
Click to expand...


Netgear R6400 connected to a Virgin Superb 2 in modem mode.

I can ping the PI on that IP and connect to it with a browser on that address, it should port forward but the router appears not to open the port.
 
Which print server are you using and how are you connecting to the Pi? web browser or terminal emulator (Putty for example)?
Are you doing all this within the same network or accessing across the internet?
 
Octoprint server

Hardwired to router

Web browser

It works fine if I try and connect locally but if I try to port forward it then connect using a browser over the internet its a no go.

If I use a port scanner it says the port is closed.
I've slept on it so round 2 tomight.
 
Do you have Dynamic DNS setup in order to map a web address to your ISP assigned ip address, Virginmedia don't assign static IP's so your IP address will change on the WAN side of the router.
 
Had the same WAN address for 3 years now so not that. I use the same WAN address for my cctv system and no problem there even with port forwarding.
 
Your lucky, I'm on VM and my IP changes every couple of months.

Not sure what else to suggest, could try using higher port number, in the thousands just to see if VM block any lower ports, (I'm assuming it's just a typo in your post above ref port 810 then 801) what does wireshark report? That may point in the right direction.
 
I used to have a port open for RDP on my VM router for remote access to a workstation and that worked fine.
Port 5589 directed to a local fixed IP inside my network.
I think you have to set a port rule.
I have a feeling you don't use port triggering.
 
ChrisH said:
Netgear R6400 connected to a Virgin Superb 2 in modem mode.

I can ping the PI on that IP and connect to it with a browser on that address, it should port forward but the router appears not to open the port.
Click to expand...
But is the pi expecting port 810 traffic? Just opening the router up won't necessarily work if there isn't a service on the pi that responds to that

Plus if the vm hub is in modem mode it won't be doing any traffic filtering. You want to change the netgear.
 
Last edited:
Cheers folks seems I'm not the only one struggling with this. I'm reading up on Raspberry Pi forums on the nitty gritty of how to turn off dhcp on the pi and give it a static address. it's bloody complicated.
 
I use a cctv application. It appears after much digging that the pi using raspbian operating system gets 2 ip addresses even if you try to give a static up. It took some digging last night and I found out even if you give it a fixed up in one file it still grabs a second via dhcp. My cctv has a fixed IP address so even if you http into it it’s ok and you can assign a port to it because it’s fixed. Because the pi gains two ip’s a fixed one and somehow a dhcp supplier on it will not port forward. The netgear router does not allow port forwarding on a dhcp address. Anyhoo I’ve manage to disable dhcp on the pi and now have it on an open port so I can see my 3D printer on line.
Wierd but it works, thanks greatly for everyone’s input.
 
You must log in or register to reply here.
Back
Top