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1. Debian Ssh Log
2. Google Cloud Debian Instance Generate Ssh Key Generator
3. Install Ssh On Debian
4. Debian Ssh Command Not Found
5. Debian Ssh Setup
6. Debian Ssh Key

need to set and test my web-app using Google cloud compute engine. How do I connect to an Instance Using ssh on Ubuntu Linux or Apple OS X based system?

Google Cloud Platform provides few methods to authenticate to a VM instances on their platform. One of them is by using SSH keys. GCP doesn’t have a way to generate SSH key pairs automatically. So users have to generate key pairs somewhere else. You’ll learn how to generate and add SSH key pair to Google Compute Engine VM instance in this post. Jul 14, 2019 You just need to generate two SSH keys (public key and private key) to connect securely to your VM instances. Generate Public and Private keys using default mac terminal. Configure Your Google Cloud VM. Connect via SSH on mac. If you need your instance to ignore project-wide public SSH keys and use only the instance-level keys, you can block project-wide public SSH keys from the instance. This allows only users whose public SSH key is stored in instance-level metadata to access the instance.

• I am trying to set up ssh keys through the Google Cloud Platform console. I made a key in Puttygen, but what is the format to paste it into the console? How do I remove the passphrase for the SSH key without having to create a new key? How to get the ssh keys for a new Google Compute Engine instance.
• To generate a new SSH key pair, you can use PuTTYgen (Windows) or the ssh-keygen command (Linux and Mac OS X). Find instructions on using PuTTYgen and instructions on using ssh-keygen. Log in to the Google Cloud Console and select your project.

By default, you can always connect to an instance using ssh. This is useful so you can manage and configure your instances beyond the basic configuration enabled by gcutil or the REST API. The easiest way to ssh into an instance is to use gcutil command from your local Linux / OS X based systems. The following steps are required

1. Install gcutil/google sdk
2. Authorize instance
3. Verify instance status
4. Create ssh keys
5. Connect using gcutil or ssh client

Step #1: Install gcutil

gcutil runs on UNIX-based operating systems such as Linux and Mac OS X. To use gcutil, you must have Python 2.6.x or 2.7.x installed on your computer. gcutil does not support Python 3.x. Python is installed by default on most Linux distributions and Mac OS X. Open the Terminal and type the following command or to grab gcutil tool visiting this url.

Debian / Ubuntu / RHEL / CentOS Linux/OS X UNIX user type the following commands:

Open a terminal and type:
## Download IT ##
$ wget https://dl.google.com/dl/cloudsdk/release/google-cloud-sdk.tar.gz
$ tar -zxvf google-cloud-sdk.tar.gz
## INSTALL IT ##
$ bash google-cloud-sdk/install.sh
Sample outputs:

See how to install gcutil tool to manage Google Compute Engine on Linux / Unix for more information.

Step #2: Authenticating to Google Compute Engine

The syntax is:

If your project id is “apache-cluster”, enter:

Sample outputs:
Open a web browser, and go to the specified URL. Click the Grant Access link. The page will display an authorization code. Copy this code. Paste the authorization code into the waiting gcutil auth terminal and press enter. Type the following command to cache project-id:

Step #3: Verify instance status

Type the following command:
$ gcloud compute instances list
Sample outputs:

Note: instance-1 instance running in asia-east1-c zone.

Step #4: Create ssh keys

The syntax is:

In this example, connect to db1 instance using ssh:
$ gcloud compute ssh db1

gcutil creates local files to store your public and private key, and copies your public key to the project. By default, gcutil stores ssh keys in the following files on your local system:

• $HOME/.ssh/google_compute_engine – Your private key
• $HOME/.ssh/google_compute_engine.pub – Your public key

Step #5: Connect using gcutil or ssh client

The syntax is:

OR

In this example, connect to the ‘instance-1’ instance using gcloud tool:

Sample outputs:

In this example, connect to the db1 (public ip 1.2.3.4) instance using ssh command:

Sample sessions:

To SSH into ‘db3’ in zone asia-east1-c, run:
gcloud compute ssh db3 --zone asia-east1-c

You can also run a command on the virtual machine. For example, to get a snapshot of the guest’s process tree, run:
gcloud compute ssh db3 --zone asia-east1-c --command 'ps -ejH'

If you are using the Google container virtual machine image, you can SSH into one of your containers with:
gcloud compute ssh db3 --zone asia-east1-c --container CONTAINER

How do I login as root user?

For security reasons, the standard Google do not provide the ability to ssh in directly as root. The instance creator and any users that were added using the –authorized_ssh_keys flag or the metadata sshKeys value are automatically administrators to the account, with the ability to run sudo without requiring a password. Type the following command to switch to root user:

Sample session:

Optional: Update your gcloud tools

Type the following command:

Sample outputs:

References:

Debian Ssh Log

• $HOME/.bash_profile file example.
• Google Compute Engine documentation.
• Man pages: bash(1)

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Introduction

SSH, or secure shell, is an encrypted protocol used to administer and communicate with servers. When working with a Debian server, chances are you will spend most of your time in a terminal session connected to your server through SSH.

In this guide, we’ll focus on setting up SSH keys for a vanilla Debian 10 installation. SSH keys provide an easy, secure way of logging into your server and are recommended for all users.

Step 1 — Create the RSA Key Pair

The first step is to create a key pair on the client machine (usually your computer):

By default ssh-keygen will create a 2048-bit RSA key pair, which is secure enough for most use cases (you may optionally pass in the -b 4096 flag to create a larger 4096-bit key).

After entering the command, you should see the following output:

Press enter to save the key pair into the .ssh/ subdirectory in your home directory, or specify an alternate path.

If you had previously generated an SSH key pair, you may see the following prompt:

Warning: If you choose to overwrite the key on disk, you will not be able to authenticate using the previous key anymore. Be very careful when selecting yes, as this is a destructive process that cannot be reversed.

You should then see the following prompt:

Here you optionally may enter a secure passphrase, which is highly recommended. A passphrase adds an additional layer of security to prevent unauthorized users from logging in. To learn more about security, consult our tutorial on How To Configure SSH Key-Based Authentication on a Linux Server.

You should then see the following output:

You now have a public and private key that you can use to authenticate. The next step is to place the public key on your server so that you can use SSH-key-based authentication to log in.

Step 2 — Copy the Public Key to Debian Server

The quickest way to copy your public key to the Debian host is to use a utility called ssh-copy-id. Due to its simplicity, this method is highly recommended if available. If you do not have ssh-copy-id available to you on your client machine, you may use one of the two alternate methods provided in this section (copying via password-based SSH, or manually copying the key).

Copying Public Key Using ssh-copy-id

The ssh-copy-id tool is included by default in many operating systems, so you may have it available on your local system. For this method to work, you must already have password-based SSH access to your server.

To use the utility, you simply need to specify the remote host that you would like to connect to and the user account that you have password SSH access to. This is the account to which your public SSH key will be copied.

The syntax is:

You may see the following message:

This means that your local computer does not recognize the remote host. This will happen the first time you connect to a new host. Type “yes” and press ENTER to continue.

Google Cloud Debian Instance Generate Ssh Key Generator

Next, the utility will scan your local account for the id_rsa.pub key that we created earlier. When it finds the key, it will prompt you for the password of the remote user’s account:

Type in the password (your typing will not be displayed for security purposes) and press ENTER. The utility will connect to the account on the remote host using the password you provided. It will then copy the contents of your ~/.ssh/id_rsa.pub key into a file in the remote account’s home ~/.ssh directory called authorized_keys.

You should see the following output:

At this point, your id_rsa.pub key has been uploaded to the remote account. You can continue on to Step 3.

Copying Public Key Using SSH

If you do not have ssh-copy-id available, but you have password-based SSH access to an account on your server, you can upload your keys using a conventional SSH method.

We can do this by using the cat command to read the contents of the public SSH key on our local computer and piping that through an SSH connection to the remote server.

On the other side, we can make sure that the ~/.ssh directory exists and has the correct permissions under the account we’re using.

We can then output the content we piped over into a file called authorized_keys within this directory. We’ll use the >> redirect symbol to append the content instead of overwriting it. This will let us add keys without destroying previously added keys.

The full command looks like this:

You may see the following message:

This means that your local computer does not recognize the remote host. This will happen the first time you connect to a new host. Type “yes” and press ENTER to continue.

Afterwards, you should be prompted to enter the remote user account password:

After entering your password, the content of your id_rsa.pub key will be copied to the end of the authorized_keys file of the remote user’s account. Continue on to Step 3 if this was successful.

Copying Public Key Manually

If you do not have password-based SSH access to your server available, you will have to complete the above process manually.

We will manually append the content of your id_rsa.pub file to the ~/.ssh/authorized_keys file on your remote machine.

To display the content of your id_rsa.pub key, type this into your local computer:

You will see the key’s content, which should look something like this:

Access your remote host using whichever method you have available.

Once you have access to your account on the remote server, you should make sure the ~/.ssh directory exists. This command will create the directory if necessary, or do nothing if it already exists:

Now, you can create or modify the authorized_keys file within this directory. You can add the contents of your id_rsa.pub file to the end of the authorized_keys file, creating it if necessary, using this command:

In the above command, substitute the public_key_string with the output from the cat ~/.ssh/id_rsa.pub command that you executed on your local system. It should start with ssh-rsa AAAA....

Finally, we’ll ensure that the ~/.ssh directory and authorized_keys file have the appropriate permissions set:

This recursively removes all “group” and “other” permissions for the ~/.ssh/ directory.

If you’re using the root account to set up keys for a user account, it’s also important that the ~/.ssh directory belongs to the user and not to root:

In this tutorial our user is named sammy but you should substitute the appropriate username into the above command.

We can now attempt passwordless authentication with our Debian server.

Step 3 — Authenticate to Debian Server Using SSH Keys

If you have successfully completed one of the procedures above, you should be able to log into the remote host without the remote account’s password.

The basic process is the same:

If this is your first time connecting to this host (if you used the last method above), you may see something like this:

This means that your local computer does not recognize the remote host. Type “yes” and then press ENTER to continue.

If you did not supply a passphrase for your private key, you will be logged in immediately. If you supplied a passphrase for the private key when you created the key, you will be prompted to enter it now (note that your keystrokes will not display in the terminal session for security). After authenticating, a new shell session should open for you with the configured account on the Debian server.

If key-based authentication was successful, continue on to learn how to further secure your system by disabling password authentication.

Step 4 — Disable Password Authentication on your Server

If you were able to log into your account using SSH without a password, you have successfully configured SSH-key-based authentication to your account. However, your password-based authentication mechanism is still active, meaning that your server is still exposed to brute-force attacks.

Before completing the steps in this section, make sure that you either have SSH-key-based authentication configured for the root account on this server, or preferably, that you have SSH-key-based authentication configured for a non-root account on this server with sudo privileges. This step will lock down password-based logins, so ensuring that you will still be able to get administrative access is crucial.

Once you’ve confirmed that your remote account has administrative privileges, log into your remote server with SSH keys, either as root or with an account with sudo privileges. Then, open up the SSH daemon’s configuration file:

Inside the file, search for a directive called PasswordAuthentication. This may be commented out. Uncomment the line and set the value to “no”. This will disable your ability to log in via SSH using account passwords:

Install Ssh On Debian

Save and close the file when you are finished by pressing CTRL + X, then Y to confirm saving the file, and finally ENTER to exit nano. To actually implement these changes, we need to restart the sshd service:

As a precaution, open up a new terminal window and test that the SSH service is functioning correctly before closing this session:

Debian Ssh Command Not Found

Once you have verified your SSH service, you can safely close all current server sessions.

Debian Ssh Setup

The SSH daemon on your Debian server now only responds to SSH keys. Password-based authentication has successfully been disabled.

Conclusion

Debian Ssh Key

You should now have SSH-key-based authentication configured on your server, allowing you to sign in without providing an account password.

If you’d like to learn more about working with SSH, take a look at our SSH Essentials Guide.