SSH Connection Issue: Local VM Connects Instead of Target VM in VirtualBox

Introduction

This article aims to help users who are experiencing an issue with SSH connections between two Ubuntu virtual machines (VMs) using VirtualBox. The problem is that instead of connecting to the target VM, the SSH client is connecting to the local VM by mistake. In this article, we will provide a detailed context of the issue, cover key concepts, and offer potential solutions.

Two Ubuntu VMs: myserver01 and myserver02

In this scenario, we have two Ubuntu VMs named myserver01 and myserver02, both running on VirtualBox. The goal is to establish an SSH connection from myserver01 to myserver02. However, when attempting the connection, the SSH client is connecting to myserver01 instead.

Misconfigured Networking

One common cause of this issue is misconfigured networking settings in VirtualBox. Ensure that both VMs have unique network interfaces and that the correct interfaces are being used for SSH connections.

Check Network Interfaces

ifconfig command can be used on both VMs to check their network interfaces. Make sure that each VM has a unique IP address and that they are not using the same IP address or subnet.

Configure Network Adapters

In VirtualBox, go to the network adapter settings for each VM and make sure that the correct adapter is selected for the SSH connection. For example, if you are using a NAT network, make sure that the NAT network adapter is selected.

VirtualBox Guest Additions

Another potential cause of the issue is the absence or incorrect installation of VirtualBox Guest Additions on the target VM. The Guest Additions provide improved graphics, mouse, and network integration between the host and the guest operating system.

Install Guest Additions

To install VirtualBox Guest Additions, follow these steps:

1. Insert the VirtualBox Guest Additions ISO file into the target VM's CD/DVD drive.
2. Open a terminal window on the target VM and run the following command:

sudo apt-get update

3. Install the necessary dependencies:

sudo apt-get install build-essential

4. Mount the VirtualBox Guest Additions ISO:

sudo mount /dev/cdrom /mnt

5. Change to the mounted directory:

cd /mnt

6. Extract the VirtualBox Guest Additions:

sudo tar -xzf VirtualBox-.tar.gz

7. Install the VirtualBox Guest Additions:

sudo ./VBoxLinuxAdditions-.run

8. Reboot the target VM.

Firewall Settings

A firewall on either the host or target VM might be blocking the SSH connection. Check the firewall settings on both machines to ensure that SSH is allowed through.

Summary

In this article, we discussed an issue where an SSH connection between two Ubuntu VMs in VirtualBox was connecting to the local VM instead of the target VM. We explored possible causes, including misconfigured networking settings, missing or incorrectly installed VirtualBox Guest Additions, and firewall settings. By following the steps outlined in this article, you should be able to resolve the issue and establish a successful SSH connection between your VMs.