Connecting to the EECS Instructional Computers

How Do I Connect over the Network?
How Do I Copy Files Between Computers?

If you are not able to utilize the bSecure VPN service, you may utilize the SSH Jumphost using SSH keys: Jumphost

• Connecting@Berkeley   Student Technology Services
• Campus Wi-Fi   wireless networks on campus
• software for logging into UNIX   ssh, putty, xming, winscp
• software for logging into Windows   Remote Desktop Client, rdesktop
• bSecure VPN   puts your remote computer on a virtual UCB network
• EECS VPN   VPN for non-Instructional EECS accounts
• file-transfers.html   for non-Instructional EECS accounts
• home-ip.help   troubleshooting tips

if you are on an EECS UNIX or macOS computer:	You can login to one of our UNIX servers using 'ssh'.   Enable X11 tunneling before you login so UNIX graphics programs can open windows on your local computer (usually 'ssh -X').   You can copy the files to other UNIX accounts using 'sftp', the SSH file transfer program, which comes with the SSH package.   See ssh.help for more information about SSH on UNIX. All EECS UNIX systems have 'ssh' and 'sftp'.   Sample usage (for user 'jdoe'): % ssh jdoe@cory.eecs.berkeley.edu % sftp jdoe@cory.eecs.berkeley.edu:public_html index.html-new On macOS, you can logon to one of our Windows servers using the Remote Desktop Connection client.   You can set it so that the disks on your local computer are connected to the logon session on our server. When you start your RDC program, type in the name of our Windows server, then select Options->Local Resources->Local devices and click on "disks", then on "Connect".   Your local disks will appear in the My Computer window on our server, and you can drag files to and from them. On other UNIX systems, you can copy files to a Windows account using the UNIX 'smbclient' command.   See samba.help for more information.   For example (for username 'jdoe'): % smbclient '\\fileservice\named' -U jdoe EECS If all this fails, you could use email or USB memory to copy the file.
if you are on a non-EECS UNIX or macOS computer:	You can login to one of our UNIX servers using 'ssh'.   Enable X11 tunneling before you login so UNIX graphics programs can open windows on your local computer (usually 'ssh -X').   You can copy the files to your EECS UNIX account using 'sftp', the SSH file transfer program, which comes with the SSH package.   Most Linux and macOS systems include SSH.   See ssh.help for more information about SSH on UNIX. See ftp.help for free programs that you can install at home and use to transfer files from your account on the instrcutional UNIX computers. On macOS, you can logon to one of our Windows servers using the Remote Desktop Connection client.   You can set it so that the disks on your local computer are connected to the logon session on our server. When you start your RDC program, type in the name of our Windows server, then select Options->Local Resources->Local devices and click on "disks", then on "Connect".   Your local disks will appear in the My Computer window on our server, and you can drag files to and from them. On other UNIX systems, there is no way to connect directly to an EECS Windows directory to access or copy files.   You cannot use 'smbclient' (see above), because the related network ports are blocked from off campus for security reasons. If all this fails, you could use email or USB memory to copy the file.
if you are on an EECS Windows computer:	You can login to one of our UNIX servers using Putty.   Enable X11 tunneling and start Xming before you login so UNIX graphics programs can open windows on your PC.   You can copy files to your EECS UNIX account using WinSCP. All EECS Windows systems have Putty, WinSCP and Xming.   You can locate the program from the Start\Programs menu. You can logon to one of our Windows servers using the Remote Desktop Connection client.   You can set it so that the disks on your local computer are connected to the logon session on our server. When you start your RDC program, type in the name of our Windows server, then select Options->Local Resources->Local devices and click on "disks", then on "Connect". Your local disks will appear in the My Computer window on our server, and you can drag files to and from them. You can connect to your UNIX home directory (the Instructional UNIX file server is "mamba").   If your username were 'jdoe', you would type this in the Windows Start->Run... text entry box: net use X: \\mamba\jdoe /user:eecs\jdoe You can connect to another EECS Windows directory (the Instructional Windows file server is "fileservice").   If your username were 'jdoe', you would type this in the Windows Start->Run... text entry box: net use Y: \\fileservice\named\jdoe /user:eecs\jdoe Here are examples of home directory paths for EECS Windows accounts: \\fileservice\named\jdoe   (Instructional named account) \\fileservice\ee20n\sp07\ee20n-ab     (Instructional class account) \\home\home\jdoe   (non-Instructional account) If you are prompted for a Username and Password, here is an example: Username: EECS\jdoe Password: [ Windows password for jdoe ] Note that Windows can remember only ONE user's permissions per file server, so if you try to connect to a second home directory on the same server, you will not be asked for another Username and Password.   Instead, you will be connected using the permissions of the first connection you made.   So it is likely that the second connection will not have full access permissions or will not be permitted at all.   The only way you can get full acess to the second home directory is to logout of Windows, login again and connect to that home directory first. If all this fails, you could use email or USB memory to copy the file.
if you are on a non-EECS Windows computer:	You can login to one of our UNIX servers using Putty.   Enable X11 tunneling and start Xming before you login so UNIX graphics programs can open windows on your PC.   You can copy files to your EECS UNIX account using WinSCP. See ftp.help for free programs that you can install at home and use to transfer files from your account on the instrcutional UNIX computers. You can logon to one of our Windows servers using the Remote Desktop Connection client.   You can set it so that the disks on your local computer are connected to the logon session on our server. When you start your RDC program, type in the name of our Windows server, then select Options->Local Resources->Local devices and click on "disks", then on "Connect". Your local disks will appear in the My Computer window on our server, and you can drag files to and from them. If all this fails, you could use email or USB memory to copy the file.
Using email or removable media to transfer files:	You can copy files by emailing the files to yourself as attachments and downloading them from the email server to the computer (UNIX or Windows) where you read the email.   Instuctional accounts can logon to imail.eecs.berkeley.edu to read and post email. See "tar.help" "man tar" and "man uuencode" for methods of bundling UNIX files for delivery by email. You can copy files to removable media such as a CD-RW or DVD-RW disk, a flash memory card or a USB memory stick.   See multimedia.help for the current location of these drives in the EECS Instructional labs.

How Do I Display UNIX Graphics to My Computer?

Summary:

Don't use the telnet programs that come with Exceed, X11, etc. X2Go is the easiest program for displaying the console of a remote Linux computer to your local Windows or Linux desktop. An alternative is to use the programs Putty and Xming. Use scp (UNIX, macOS) or WinSCP (Windows) to transfer files bewteen computers.

You can login to our UNIX systems and run programs there that display their graphical output on your computer screen. To do this, you need an XWindows server running on your computer.   You can download Putty, WinSCP and Xming for this.

To login to UNIX/Linux and run XWindows programs from a Windows computer, follow these steps:

1. Open a 'Putty' window on the PC, enable "X11 Forwarding" and login to your UNIX account.
2. Start 'Xming' on the PC.
3. To verify that you have X11 working, type an XWindows command such as "xterm" at the UNIX command line in the Putty window.   A window from the UNIX system should pop up on your screen.   Note that the Xll tunneling sets the UNIX DISPLAY variable to something with "localhost" in it, and you should not change that.   You can verify that it is set right by typing "printenv DISPLAY" in the Putty window.

Troubleshooting XWindows problems:

Here are some common errors and their causes.

Problem:	Possible Causes:	Solutions:
You type the UNIX command (such as "xterm") and you get an error similar to X connection to 128.32.138.27:11.0 broken (explicit kill or server shutdown).	An XWindows server (Xming, XDarwin, etc) is not running on your local computer. The .Xauthority file in the user's UNIX directory is old. The UNIX account is over its disk quota; this prevents the .Xauthority file from being written. Your firewall is blocking it.	Start an XWindows server on your desktop computer. Delete .Xauthority file in your UNIX acocunt; login again to UNIX account. Reduce UNIX disk usage and login to the UNIX account again. Turn off the firewall and try again.   If that fixes it, then turn the firewall back on and enable the XWindows server (Xming, Exceed, etc). (For the Symantec filewall, turn off "auto protect" and tell it to alert you when it blocks something, so you'll get a chance to "allow" the XWindows connections.)
You type the UNIX command (such as "xterm") and you get an error similar to Error: Can't open display: OR Error: Can't open display: cory.eecs.berkeley.edu:0.0	"X11 Forwarding" is not enabled in the Ssh window. You have an old 'setenv DISPLAY' command in your .cshrc or .login file.	Logout from UNIX, enable "X11 Forwarding", login again. Remove all hard-coded 'setenv DISPLAY' commands, logout, login again.
You type "emacs &" and it just hangs for 30 seconds to a minute, then you are disconnected from the server you are logged onto.	"X11 Forwarding" is enabled in the Ssh window but you are not running an XWindows server. You have an old 'setenv DISPLAY' command in your .cshrc or .login file.	Run the command "emacs -nw &"   (-nw = 'no windows'). or Run the command "emacs"   (without the &) so you can see any error messages. Remove all hard-coded 'setenv DISPLAY' commands, logout, login again.

How Do I Find Software?

How Do I Access on-line Discussions?

Ed Discussion	Create an account and password for yourself there, then ask your instructor for the name of the course so you can "enroll" in it there. An enrollment roster can't be attached to Piazza, so the students have to sign up for it themselves. Typically, the instructor will send an email to the class inviting them to register for the class in Piazza.
bCourses	This is the UC Berkeley course management system.   Login to this server using your UC Berkeley CalNet ID.   On bCourses, the Discsussions and Collaborations tools are useful for group communication.   Unlike USENET and Google Groups, this server will not receive spam.
Google Groups	This service duplicates postings from USENET news servers. The contents may not be real-time copies of the source. It is free, but some users are sceptical about the privacy of data stored where the vendor may reveal it to advertisers.
Usenet, Supernews	Fee-based USENET services.

How Can I Be Sure My Password and Files are Private?

Questions about SSH:	Answers:
1. Is the "pass phrase" like the password on a UNIX account? Does it need to be long, and with nonalphabetic characters etc.? What happens if someone guesses it?	1. Passphrase is like a password, which is used to enable increased security (it is not required). "ssh-keygen" creates it. The UNIX "man ssh-keygen" command says "The passphrase may be empty to indicate no passphrase (host keys must have empty passphrase), or it may be a string of arbitrary length. Good passphrases are 10-30 characters long and are not simple sentences or otherwise easily guessable..." If someone guesses it, they can login to your account and do bad things.
2. Suppose you work on more than two accounts (for example: my home Mac, my campus Mac, my hera account, from which I access a variety of other accounts). Will one key suffice for the various accounts that I use for initial login, or should I have different keys?	2. The SSH "key" files are stored in files in your .ssh subdirectory on UNIX, or in your UserKeys folder on Windows. The files could be unique in each account, or they could be copied (do it securely using scp!) to other accounts.
3. Every time I login with ssh, I get the message that hera is sending a previously unknown key (or some such thing). What's going on here, and what's the proper response?	3. If you answer "yes" to the question, ssh will add the key of the remote host (ie "hera") to your ~/.ssh/known_hosts file (UNIX) and you won't be asked again, unless they change the host key on hera (or someone is pretending to be hera on the network).

How Do I Set an Additional Password or Password-less Access to my Account?