Ubuntu Networking :: Router Port Forwarding For Ssh
Aug 22, 2010
I have logged into my router and set up port-forwarding on port 22. I can log into the machine fine from a machine on the local network using the machines internal IP but when I try to log on from a remote machine using my router's external IP or my DyDNS host-name I get a message saying "connection refused" or "connection timed out." I have configured port-forwarding on the router and the firewall rules says that port 22 is open but when I nmap my routers external ip it says that only port 23 and 80 are open. I am very new to linux and networking.
I have the wake on lan option enabled on my debian computer. If i wake it by sending:
-mac adres -internal ip in my home network -subnetmask -port 7
It all works fine, but when i try to do it from outside my network and change the ip address to the router adress it wont go on. I have also opened the port 7 in my router.
I'm trying to get my SSH server I set up on my home box working from behind a router. A 2wire 2700HG-B gateway, in fact. Now, I know my server is working fine, because I can get into it via loopback, anywhere inside the LAN from another machine, OR if I go into the router's config and enable DMZ for the machine. However, I don't like having DMZ on all the time because of the kludge-ness of it, and the security issue of the complete absence of a hardware firewall.If I try to port forward and access it from outside the LAN using the external IP (or my DynDNS, because it's dynamic), it just times out. I have a nonstandard port (45) for the listen port of the server, to keep away hack attempts if I were using the standard 22. I used this to see if the port was open, and it said it was. But, I tried the trick of telnetting the IP with that port, and it also timed out, instead of printing stuff about OpenSSH.
Attached is a screenie of my router's firewall page, so you all can look at it and see if I'm an idiot and doing it wrong. You might notice uTorrent there, it's because this machine is a dual-boot with 7, and the router doesn't differentiate the OS's. Also the SSH @ 46 port is for the Windows side, with freeSSHd. I changed the port on that one so the client I have can distinguish them, so it can run a reachability test.
what I have: Belkin G Wireless Router Model F5D7234-4. To attempt to get Subsonic working, I changed the port forwarding settings (Belkin calls it Virtual Servers) to forward port 4040 to my desktop computer. I then saved changes, and my wireless disconnected. I waited about 3 minutes, and nothing was happening, so I restarted my router. This left me in the position that I am in now. Even when the router and modem are fully booted, the router does not broadcast my SSID. In addition, a wired connection will not connect to the network through the router. This leaves me completely unable to use wireless, and unable to change any settings in the router.
I've managed to confirm that I can reach my home network via ssh from a remote location through my SMC Barricade when it is directly connected to the desktop machine but when the second router is put back into the chain ssh requests time out. The second router is a Linksys WRT 54GL running the Tomato firmware. The chain looks like this: ISP's router (bridged) --> Barricade -->WRT54GL-->desktop
The Barricade has port 22 forwarded to the Linksys' WAN address and it in turn forwards to the desktop address. It appears that it is a setting on the Linksys firmware that is preventing the remote connection. I've looked through the various settings many times but cannot see anything that would cause the problem.
I have just set up shorewall on my router running Arch Linux. The external network is on eth0 and the internal network on eth1.I have set it up for masquerading and that works fine and I can open ports to the firewall. But I'm having trouble with port forwarding to my internal machines.The problem I have is that when port 22350 is forwarded to 192.168.1.3 on my local network, checking the port with nmap from a remote computer gives me:
I'm running suse 11.1 which is configured as a router. Configured are two DSL connections with static IP's and one LAN connection (3 NIC's all together).
Problem: suse firewall will only port forward connections from one of the DSL connections and not the other.
Because I'm running two DSL connections is there something special I have to turn on/enable on the firewall?
Say I have Computer A behind a router with NAT. I'm unable to add any port forwarding rules to that router. Then I have Computer B with a public IP address that I want to forward X windows from. This computer is headless, but does have a video card so X windows can be used. Here are some of the things I'd perform to setup my scenario.
1. Computer B, I'd run xhost + public_ip of NAT router. 2. Make sure that computer B's sshd service has X11 forwarding enabled. 3. SSH from Computer A to Computer B with the X windows forward option. 4. Once in Computer B, set the DISPLAY env variable to the public_ip of NAT router. 5. On Computer B run xclock.
At this point I'd expect to see an instance of xclock originating from Computer B onto my desktop. However this obviously won't work. The problem is that when the request is made to Computer B to forward the instance of xclock to Computer A the forwarded instance of xclock will get stuck at the NAT router. Without a port forwarding rule the NAT router will not know which internal IP to route the instance of xclock.
Here's my question. Is there any way for Computer A to initiate a connection to Computer B and then forward the instance of xclock? That way if it uses that same connection the NAT router will know which internal IP to route it to because it would be an active connection in the router's routing table. Or is there an alternative? Of course I can vnc into another computer outside the NAT network and then forward an X window to it just fine. But in the spirit of expanding my knowledge on X windows I'd like to see what is possible.
1. Need to connect 2 CCTV DVRs and view from remote. 2. Can get a static IP address. But I dont know if this is a secure way since any once can view if the know the ip address. 3. Question is : is it possible to connect the DVR( s) to a linux server which will get user name and password before letting us view the DVR. Currently there is one set as follows: 1. From location X a device is connected to location Y using leased line and static IP (12 kms distance). In location Y a router is placed and port forwarding is configured. From Location Z using internet and remote desktop concept the device at location X is viewed and data captured. Is it possible to use a similar concept but with some sort of security authentication procedure in place.
everything works fine. I can log in, and local port forwarding is done. Otherwise when I use the command:
ssh user@ssh_server -R 5500:localhost:5500 -p 22
I get an error "remote port forwarding failed for listen port 5500". However when I try remote port forwarding in WinXP by use of putty there is no problem...
I have a mail server on which I would like to block port 25 on my eth0 for everyone except our external spam filter. the problem is that I want our users to be able to connect via port 10025 which is forwarded to port 25, which then is blocked...
what should I add/change to set up port forwarding of port 1000 to ip 192.168.1.200. also how to get the answer sent by 192.168.1.200 follow the same route used by the data received through port forwarding.
As it stands I have a small home network operating behind my modem/router. Some of the ports on this are forwarded to my PS3 for gaming but I was looking at forward some for my file server.
At the moment I've forwarded port xxx22 to port 22 on my server for SSH for instance. ANd similarly 21 for FTP (although it doesnt seem to want to connect for any more than a few seconds using that). What I was thinking of doing was placing a small website for a handful of ppl to use on the server too and port forward again - xxx80 to 80. It works just fine but I'm a little concerned on the security front.
As I've moved the port to something different from the outside world I'm presuming I will have already cut the potential for malicious folks to wander in but is there anything else I should be doing? At the moment there's no firewall operating on the server, usually as its hidden behind the modem/router. But if I open this thign up more permanently what should I be doing? I've read a few articles on it but I'm always left with the overwhelming thought of "Thats if theres no firewall in my router" as they just seem to do the same.
I have a ubuntu 9.10 on my desktop in my office and I have another ubuntu on my home desktop. Both machines are behind a router. I guess many people have already asked the same question: how to remote control the office desktop from my home desktop?Many posts discussed about solving this by setting up ssh and port forwarding. But my situation is that I cannot control the router in my office so I cannot set up any port forwarding for my office desktop. So I guess my question becomes how to remote control my office desktop without setting up any port forwarding on the office router.
I currently use a commercial VPN when working overseas for secure internet access.
I now also need to VNC to a home ubuntu desktop (which runs software 24/7 that I need to periodically check).
When overseas, I use a Ubuntu laptop and an Android tablet.
For the VNC I intend to use an SSH tunnel. So my question is: should I ALSO set up openVPN on the home computer (so I can stop paying for a commercial provider which routes all my traffic twice across the Atlantic...) or is it easier/better to use the SSH tunnel for the secure webbrowsing too? Something like a SOCKS proxy?
I have a script to establish a reverse tunnel with other machine,My problem is to stop the tunnel. If I just kill the PID at sshtunnel.pids, ssh does not release the ports at the server side, so any new connection will fail for several minutes.Is there any way to signal SSH to exit gracefully?
This should be easy but for some reason its not working. I don't have admin rights on one of my local networks to open the firewall for port 80 to make my server accessible remotely (from the internet). I have a remote server (OpenVZ VPS) and I want to port forward so that [url]:8080 will point to my localhost:80 from the internet itself (i can get it to work on the remote VPS server's local network)...
How could I accomplish this? Basically, I am trying to serve webpages from behind a firewall using a VPS as a hub.
would it be possible for anyone to give me step-by-step instructions on how to set up port forwarding on my laptop? I've been using Karmic Koala and just upgraded to Lucid Lynx and not really bothered to port-forward before, so not too sure where to start - googling gives me a lot of terms I don't understand.
I have two nic cards installed in a Lucid LTS server.
eth0 is static using address 192.168.0.235 gateway 192.168.0.1 netmask 255.255.255.0
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I have my Qwest DSL modem port forwarding port 80 to 192.168.3.235 however this doesn't seem to work if I have both cards running. If I remove the second card (eth1) and reconfigure eth0 to use 192.168.3.235 I can port forward into my webserver.
I've used wake on lan and SSH on the local network for some time now. I also used SSH to mount a filesystem (SSHFS / sftp, same thing, right?) and I could forward X11, loved it. I used both these options for my convenience. So I decided it was time to open up some ports on my router (Linksys WRT320n running dd-wrt) and try to set up a remote connection. This actually worked after some time, so I'm now able to turn on my home computer from the Internet (school in my case) and then log in to it through SSH. I set this up using other ports then the default ports. Something like this (these are not the actual ports I use, just examples):
port 2112 -> port 9 (for wol, wake on lan) port 2113 -> port 22 (for SSH)
This information might be useful: I set this up using public and private keys. This is necessary for SSHFS to work properly I think and it also makes it more secure. And then I found (and had some presumptions that this was going to happen) that both SSHFS and X11 were not working. I'd rather not open up more ports on the router for security's sake though, so I'm asking for other solutions. And if there really aren't any other solutions then which ports to forward. And if forwarding is really necessarily then how to make the client use port 2114 for SSHFS and 2115 for X11 so I can forward those ports to the default ports.
I'm trying to set up very simple UDP port forwarding, but can't seem to have good results. I read trough netcat and iptables manuals, but can't seem to figure things out. my setup is the following:
I have machine1, listening on UDP port 49000. I have machine_fw, which accepts connections on 59000, and forwards all this to machine1:49000 (and returning traffic too) I have machine2, which will connect to machine_fw:59000, and this way communicate at the end with machine1:49000, as machine_fw is taking care of forwarding is there an easy way to achieve this?
I don't understand the concept of ssh port forwarding and tunneling.I was going to set up a remote desktop (vnc) connection to my grandmother's laptop that we'll give her soon so if something goes wrong i can fix it from here (she lives on the other side of the world). However, i've read using vnc plain over the internet isn't secure, and that i can secure it by running it through an ssh tunnel.That's what i've understood so far. However, from there on i get confused.
I'd have to run both an ssh server AND a vnc server on her laptop? So what i'd have to do is ssh into her computer, and then while logged on on her computer, somehow open a vnc connection back from the remote server to the local computer? Then i'd go back to my local computer and open a port where the vnc connection is waiting? From the concept, it would seem like i should be able to tunnel all the regular network traffic from the local computer to the remote one through ssh?
We have one linux machine in the office which happens to be an important firewall. I just know the basics and need to make one changeEssentially it is forward mysql traffic to another internal machine.This is the original rule (forward to 192.20.0.17) which is working
I have my mail application running on xxxx port in IPv6 and IPv4 enviornment on Linux machine (RHEL 5).I want to forward IPv4 request comming from windows client
I have a CentOS box which is Internet Facing. It has 3 LAN's connected to it which are for virtual machines.
I want to port forward port 445 to a machine on one of the LAN interfaces. I have tried various ways to get it done, but still cannot access that port from the interface. I definately know device hosting port 445 is live, as I can ping it from the CentOS box and use lynx to access it! (It's a web server)
I've been Googling about port forwarding iptables and even though there's result and I've applied it in my script, I can't make iptables forwading request to another machine so I decided to ask help.
eth0 is my Internet Interface (1.2.3.4 is the public ip) eth1 is my Lan Interface eth2 is my DMZ Interface
I have two PC's, one with slackware and one with arch, and I am trying to access the web server from the archlinux machine but i haven't manage to do that. The archlinux machine is connect to the internet via the slackware machine via a crossover cable: internet > eth0 (pc1) and ppp0 (the PPPoE connection, pc1) > eth1 (pc1) > eth0 (pc2)
pc2: ifconfig eth0 192.168.0.2 netmask 255.255.255.0 ifconfig eth0 up route add default gw 192.168.0.1 eth0 /etc/resolv.conf (The same DNS as the first PC)
And now the internet is working and on the archlinux machine, but I am not able to access the web server from LAN with a public IP. I tried many iptables port forwarding commands but none worked.
I have a server running debian squeeze and kvm to virtualize a Windoze box. It's setup to use NAT. This is because of limits on the network by the admin and unfortunately, there isn't a way to get around this.
