Logging into Server
Overview
Teaching: 5 min
Exercises: 5 minQuestions
How do I connect to a Linux server?
Objectives
Log onto to a running server
Log off from a running server
Logging into a Linux Server
To access the pre-configured workshop data, you’ll need to use our log-in credentials (user name and password). A username will be assigned to you at the workshop. In the following, always replace molepi30 with your user name and the password with the password assigned to you.
Log-in Credentials (case-sensitive!)
- Username: molepi30
- Password: password
But first, you need a place to log into! To find the server that holds your data, you’ll need the host name of the server. Your instructor should have given this to you at the beginning of the workshop.
A hostname is a label that is assigned to a device connected to a computer network and that is used to identify the server.
Connection Protocols
We will use a protocol called Secure Shell (SSH) that, as the name implies, provides you with a secure way to use a shell. In our case, the shell will be running on a remote machine. This protocol is available for every operating system, but sometimes requires additional software.
Logging onto a server
Please select the platform you wish to use for the exercises:
Exercises
Connecting using PC
Prerequisites: You must have an SSH client. There are several free options but you should have installed [PuTTY.exe] at the begining of the workshop, and we’re going to continue using that.
A. Open PuTTY; In the ‘Host Name (or IP address)’ section paste in the IP address provided by your instructor. Keep the default selection ‘SSH’ and Port (22).
B. Click ‘Open’ and you will be presented with a security warning. Select ‘Yes’ to continue to connect.
C. In the final step, you will be asked to provide a login and password. Note: When typing your password, it is common in Unix/Linux not see see any asterisks (e.g. **) or moving cursors. Just continue typing.
D. You should now be connected!
Connecting using Mac/Linux
Prerequisites: Mac and Linux operating systems will already have terminals installed. Simply search for ‘Terminal’ and/or look for the terminal icon.
A. Open the terminal and type the following command substituting ‘ip_address’ for the IP address your instructor will provide. Be sure to pay attention to capitalization and spaces
$ ssh molepi30@ip_address
B. You will receive a security message that looks something like the message below. Type ‘yes’ to proceed.
The authenticity of host 'ec2-52-91-14-206.compute-1.amazonaws.com (52.91.14.206)' can't be established.
ECDSA key fingerprint is SHA256:S2mMV8mCThjJHm0sUmK2iOE5DBqs8HiJr6pL3x/XxkI.
Are you sure you want to continue connecting (yes/no)?
C. In the final step, you will be asked to provide a login and password. Note: When typing your password, it is common in Unix/Linux not see any asterisks (e.g. **) or moving cursors. Just continue typing.
D. You should now be connected!
Logging off a server
Logging off the server is a lot like logging out of your local computer: it stops any processes that are currently running, but doesn’t shut the computer off.
To log off, use the exit command in the same terminal you connected with. This will close the connection, and your terminal will go back to showing your local computer:
molepi30@ip-172-31-62-209 $ exit
Amandas-MacBook-Pro-3 $
Logging back in
Internet connections can be slow or unstable. If you’re just browsing the internet, that means you have reload pages, or wait for pictures to load. When you’re working in cloud, that means you’ll sometimes be suddenly disconnected from the server when you weren’t expecting it. Even on the best internet connections, your signal will occasionally drop, so it’s good to know the above SSH steps, and be able to log into the server without looking up the instructions each time.
In the next section, we’ll also show you some programs that you can use to keep your processes going even if your connection drops. But for now, just practice logging on and off a few times.
Key Points
You can use putty to log in to a server
Logging off a server is not the same as turning off a server