VirtualBox port forwarding not working with NAT adapter - networking

Question

I'm trying simple port forwarding with VirtualBox and it appears VirtualBox.exe is listening on the host to the port, but not actually forwarding the connection to the guest. I've tried on multiple ports, and I've restarted VirtualBox several times. Guest to host connectivity, on the other hand, is fine. Here's the info:
Host: Win7 x64
Guest: Win7 x64
VirtualBox version: VirtualBox 4.2.10
Firewalls: All firewalls on host and guest disabled.
Virtual Box > Machine Settings > Network
Adapter 1:
Attached to: NAT
Cable Connected : True
Port Forwarding:
Rule 1: TCP, HostIP=127.0.0.1, HostPort=8081, GuestIP=127.0.0.1, GuestPort=8081
On Host:
[VirtualBox.exe] TCP 127.0.0.1:8081 IBM-6KT5OPCF76P:0 LISTENING
On Guest:
I never get the connection request on port 8081 or any others I've tried.
Any ideas? I'd like to avoid using VirtualBox's bridged adapter for multiple reasons. I was under the impression that NAT port forwarding was relatively straightforward with VirtualBox.
Thanks!

Answer 1

Paravirtualized Network* (virtio-net) is the key
select your vm that you want for port forwarding.
NOTE: Make sure the vm is in stop mode.
Select “Settings"
Select “Network"
Select any free Adapter. Lets say "Adapter 2"
Enable "Enable Network Adapter"
In Attached to dropdown, select "NAT"
Select "Advanced"
In Adapter Type: Select “Paravirtualized Network (virtio-net)” [ This is important ]
Select “Port Forwarding"
In Right hand part of the “port forwarding” dialog box, select “+"
Provide the
Name: Anything you want. example for ssh, say “ssh"
Protocol: Type of protocol [ for ssh: TCP ]
Host IP: provide hostname from which host you want to connect to [ over here: 127.0.0.1 ]
Host Port: On what port of that Host you want to connect to remote port [ example: 60022 ]
Guest IP: Leave it Blank
Guest Port: To what port you want to connect from the above host. [ for ssh, the default 22 ]

Answer 2

You've pointed guest ip in wrong manner it should be ip of guest (if you're statically assign ip address to guest) or leave it empty. Note you're pointed host ip as 127.0.0.1 it means that port you're forwarding will be accessible only from port (if it isn't what you're desired it should be empty as well).
VBoxManage modifyvm "win" --natpf1 ",tcp,,8081,,8081"
perhaps this is something you've wanted to do. (please look here for more details)

Answer 3

It is not clear which guest OS you are using.
I have faced the same problem.
My host was MAC PC and guest was CentOS 7 on VirtualBox.
I enabled the NAT port forwarding from guest to host at VirtualBox level for both ssh port 22 and http port 80.
However I found that I could not connect to the Apache HTTP server on Centos 7 guest from my MAC PC host on http connection.
To fix it, I have to set the firewalld service to allow port 80 connections.

Answer 4

Faced similar issue on Mac host, Fedora guest setup. Was trying to access http web server running on port 8000 of guest machine from host machine. Opening port 8000/tcp with firewall-cmd on guest machine solved problem.
sudo firewall-cmd --zone=public --add-port=8000/tcp

Answer 5

I faced a similar issue and it turns out to be unsigned drivers in the network stack installed by some corporate proxy interception software called proxycap that were causing virtualbox to error when setting up port forwarding. Check you VM machine logs for the error message while setting up port forwarding and listing the unsigned drivers and uninstall the corresponding application.

Answer 6

I connect to my Centos7 like this:
Virtual Box > Machine Settings > Network
Adapter 1:
Attached to: NAT
Cable Connected : True
Port Forwarding:
Rule 1: TCP, HostIP=127.0.0.1, HostPort=8081, GuestIP=10.0.2.15, GuestPort=8081
$> ssh -p8081 [change]#127.0.0.1

Answer 7

In case someone else met same problem with me, I wrote my mistake here:
I am using CentOS 7 as host and Windows as guest.
The only problem block me was: I forgot to disable Windows firewall settings in guest machine. Once disable it, everything works fine.

Answer 8

If anyone is having same issues, try to uninstall redirectors such as ProxyCap, proxifier, etc. VirtualBox NAT doesn't work with them. You won't find any error message in the logs and you won't see anything in the pcap file if you try to trace VirtualBox networking. Disabling ProxyCap is not enough, it has to be uninstalled or you need to reset your network config with "netsh winsock reset" but ProxyCap won't work for you anymore.

Answer 9

For GNU/Linux users, don't forget the first 1024 ports are restricted to the root user…
If you try forwarding a port lower than 1024, it won't even appear as LISTENING with netstat.

Answer 10

In my case the guest OS is CentOS8, the host OS is Ubuntu 22.04, the forwarded port was 1022 on the host, I changed it to 10022 then it worked.