What Is the Process to SSH Into an Ubuntu Server in Go

In this guide, we will demonstrate how to SSH into an Ubuntu server once it has been provisioned using Pulumi in TypeScript. Pulumi is used to automate the setup of an EC2 instance on AWS, including configuring the necessary security group and managing the SSH key pair for secure access. The key services involved in this process are AWS EC2 for the virtual server, AWS VPC for networking, and AWS IAM for managing the SSH key pair.

Introduction

This solution uses Pulumi to automate the provisioning of an Ubuntu server on AWS and configure it for SSH access. Pulumi is an Infrastructure as Code (IaC) tool that allows you to define and manage cloud resources using familiar programming languages like TypeScript. Through Pulumi, you can write code to create and configure an EC2 instance, set up a security group to allow SSH access, and manage the SSH key pair for secure login.

Step-by-Step Explanation

Step 1: Set Up Pulumi Project

1. Install the Pulumi CLI and configure your AWS credentials.
2. Create a new Pulumi project using TypeScript.
3. Install the necessary Pulumi AWS package.

Step 2: Create an SSH Key Pair

1. Use the AWS IAM service to create an SSH key pair.
2. Store the private key securely for later use.

Step 3: Create a Security Group

1. Define a security group that allows inbound SSH traffic on port 22.
2. Attach the security group to the EC2 instance.

Step 4: Provision the EC2 Instance

1. Define the EC2 instance resource with the desired Ubuntu AMI.
2. Attach the previously created SSH key pair to the instance.
3. Attach the security group to the instance.

Step 5: Output the Instance Details

1. Output the public IP address of the EC2 instance.
2. Use the public IP address and the private key to SSH into the instance.

SSHing Into the Ubuntu Server Using Go

Once the server is provisioned, you can SSH into it using Go. Here is a basic approach:

1. Install Go SSH Package: Ensure you have the Go SSH package installed, which can be done using go get golang.org/x/crypto/ssh.

2. Write the SSH Client Code:

   • Import the necessary packages.
   • Use the SSH private key to authenticate.
   • Connect to the server using the public IP address and execute commands.

package main

import (
    "golang.org/x/crypto/ssh"
    "io/ioutil"
    "log"
    "os"
)

func main() {
    key, err := ioutil.ReadFile("/path/to/your/private/key")
    if err != nil {
        log.Fatalf("unable to read private key: %v", err)
    }

    signer, err := ssh.ParsePrivateKey(key)
    if err != nil {
        log.Fatalf("unable to parse private key: %v", err)
    }

    config := &ssh.ClientConfig{
        User: "ubuntu",
        Auth: []ssh.AuthMethod{
            ssh.PublicKeys(signer),
        },
        HostKeyCallback: ssh.InsecureIgnoreHostKey(),
    }

    client, err := ssh.Dial("tcp", "<INSTANCE_PUBLIC_IP>:22", config)
    if err != nil {
        log.Fatalf("failed to dial: %v", err)
    }
    defer client.Close()

    session, err := client.NewSession()
    if err != nil {
        log.Fatalf("failed to create session: %v", err)
    }
    defer session.Close()

    session.Stdout = os.Stdout
    session.Stderr = os.Stderr
    session.Run("echo 'Hello, Ubuntu!'")
}

Key Points

• Pulumi allows you to define and manage cloud resources using TypeScript.
• AWS EC2 is used to provision the Ubuntu server.
• AWS VPC is used for networking and security group configuration.
• AWS IAM is used to manage the SSH key pair.
• Ensure that the private key is stored securely and not exposed.

Conclusion

By following this guide, you have successfully provisioned an Ubuntu server on AWS using Pulumi in TypeScript and configured it for SSH access. While Pulumi handles the provisioning, you can use Go to establish an SSH connection to the server. Pulumi simplifies the process of managing cloud infrastructure by allowing you to use familiar programming languages and providing seamless integration with cloud providers like AWS. With this setup, you can easily automate the provisioning and configuration of servers and other cloud resources.

Full Code Example

import * as pulumi from "@pulumi/pulumi";
import * as aws from "@pulumi/aws";

// Create an SSH key pair
const keyPair = new aws.ec2.KeyPair("my-key-pair", {
    publicKey: "<YOUR_PUBLIC_KEY_HERE>",
});

// Create a security group that allows SSH access
const securityGroup = new aws.ec2.SecurityGroup("my-security-group", {
    ingress: [
        {
            protocol: "tcp",
            fromPort: 22,
            toPort: 22,
            cidrBlocks: ["0.0.0.0/0"],
        },
    ],
});

// Create an EC2 instance
const instance = new aws.ec2.Instance("my-instance", {
    instanceType: "t2.micro",
    ami: "ami-0c55b159cbfafe1f0", // Ubuntu Server 20.04 LTS (HVM), SSD Volume Type
    keyName: keyPair.keyName,
    vpcSecurityGroupIds: [securityGroup.id],
    tags: {
        Name: "my-instance",
    },
});

// Export the public IP of the instance
export const instancePublicIp = instance.publicIp;