Logging in Remotely

You are not required to actually sit down in front of a workstation to use our computers. You can log in from your dorm, home, Europe, or even in the middle of College Green using the wireless network. All you require is your login and password, and a communication program called ssh.

Ssh is a program that connects your computer with another computer, and encrypts the communications while doing so. This is done so that if someone intercepts your session (or when someone does in the case of wireless) they will be unable to decode what is sent between the computers. Older forms of communication such as telnet and ftp do not encrypt the session, so that anyone intercepting your communication can easily steal your login and password.

When you connect to one of our machines, you will be asked for you login and password. Just enter your login and password (you will not be able to see your password as you type). You will then be logged on with the same prompt as you would see in a terminal or console window on the workstation.

To log off, use the exit command, or just type CNTRL-D.

To copy files from one machine to another, use the scp command. See the man page for more information.

Obtaining ssh

If you have a Mac or Linux box, you probably already have ssh (and scp) installed. Just bring up a terminal window, and type ssh MACHINE_NAME to ssh into the machine name of your choice.

For Windows users, one of the popular versions is PuTTY available at http://www.chiark.greenend.org.uk/~sgtatham/putty/ Putty has a command line verison of scp named PSCP, but a more Windows friendly program for copying files to/from Windows and our Unix systems ins WinSCP, available at http://winscp.net/eng/index.php Winscp his program allows you to open a window on your pc and browse the files on the server just like it was a local disk. Drag-and-drop copy between machines is supported, as well as advanced features such as automatically syncing the files on the server to your pc - great for backing up critical directories.

Note that you do not log into prime itself to transfer files but one of our other machines.

Using ssh without a password

You can use ssh to connect to our servers or the machines in the labs without using a password. You have to create a public/private key pair in your .ssh directory. To do this, run the commands:
ssh-keygen -t rsa -b 4096
cp ~/.ssh/id_dsa.pub ~/.ssh/authorized_keys
chmod 700 ~/.ssh
and now you can ssh directory to any of our lab machines or servers from any of the other machines.

To use a differenet machine to login to the EECS machines without a password, run the ssh-keygen program on that machine, then add the id_dsa.pub file to your authorized_keys file.

One special note: the machine ace.cs.ohiou.edu is not on the prime ring of machines. However, it does host our web server, so you may want to use it from a prime machine. Just add the contents of the id_dsa.pub file you created above to the authorized_keys file on ace and you can login without needed a password >/p>