CTC: Accessing CTC Machines

There are three main ways in which you can get access to CTC login machines and fileservers. These are Remote Desktop Connection, SSH, and Drag-and-Drop Files.

Login ID

To login to a CTC machine, enter your_userid@tc.cornell.edu as the User name.

Remote Desktop Connection (preferred)

Login machines
This method of connecting to the login machines (winlogin1, winlogin2) is preferred because it provides you with a fully functional Windows desktop. At the login screen, "Log on to" should be CTC_ITH , not the name of the machine to which you are connecting.

Batch machines
Once you have established a remote desktop connection to a login machine, you can use a remote desktop connection to connect to a batch machine on which you have a running job. You cannot use telnet. These machines provide a command line interface, plus the normal graphical user interface for individual applications. To leave the batch machine, type logoff or shutdown -l at a command prompt.

If you use a Windows machine: Use the Remote Desktop Connection (older name Terminal Services Client) to connect to a login machine. This software is pre-installed with Windows XP. To run it, click Start, then All Programs, Accessories, Communications, and Remote Desktop Connection. Otherwise you need to download the client before you can use it.
NOTE: If you are a local administrator on your computer and are running Internet Explorer 5 or later, you can use the Remote Desktop Web Connection. This web interface is called TSWeb and can be accessed at http://www.tc.cornell.edu/tsweb. Enter the name of a login machine in the Server box and choose your preferred screen size. If you choose Full Screen you can toggle between your Remote Desktop session and your desktop by hitting Ctrl Alt Pause simultaneously. Hit connect and you will be brought to a Windows login screen, where you can log in as you normally would.
If you use Mac OS X v.10.2.8 or later: Use the free download from http://www.microsoft.com/mac/download/misc/RDC.asp. Works just like the Remote Desktop Connection in Windows XP. You can also use rdesktop (see below).
If you use Unix or Linux or Mac: You can access the login machines by using the cross-platform rdesktop client. If you are running Linux, typically it is part of the distribution. If you prefer to build it yourself, it is available for download from http://www.rdesktop.org/. Executables are available from http://www.jacco2.dds.nl/rdesktop/index.html.

SSH and Friends

SSH/telnet
You cannot telnet to any CTC machine. This method is insecure. Use SSH to connect to the login machines. SSH cannot be used to connect to the batch machines. If you want to connect to a batch machine, use a Remote Desktop connection to a login machine, then another Remote Desktop connection to a batch machine.
sftp/ftp
Use sftp for secure file transfers. Since ftp is not secure, it has been disabled as a method to access the login machines for file transfer.
SSH Servers
The SSH servers are now the login nodes winlogin1.tc.cornell.edu and winlogin2.tc.cornell.edu. Since SSH makes a distinction between winlogin1.tc.cornell.edu and winlogin1, be consistent. To be on the safe side, use the fully qualified server names. These are the only 2 CTC Windows machines to which you can connect with SSH.
SSH Clients
Must support the SSH2 implementation.

For Windows, H:\CTC Tools contains the installation executable SSHWinClient.exe (for ssh2/sftp2/scp2) and puTTY.

Instructions on installing SSHWinClient.exe .

Details on using the SSH GUI.

Other sites from which ssh clients can be downloaded:

SSH Secure Shell
At this site the file to download is
ftp://ftp.ssh.com/pub/ssh/SSHSecureShellClient-3.2.9.exe.
Open SSH
puTTY

Scroll Bars in SSH
To obtain a scroll bar in the window can sometimes require settings that are different from the defaults.

SSH Secure Shell
Edit -> Settings -> Profile Settings ->
Connection, set Terminal answerback to tty

Keyboard, check Enter sends CR and LF

puTTY
After invoking puTTY from the command line
Connection -> Terminal Type String -> tty
Terminal -> check box "Implicit CR in every LF"

Windows command line in SSH
To get the correct formatting of the screen, set term=tty before issuing "ssh2 winlogin1".

It does not yet have file completion and the up/down arrows do not retrieve commands. We are looking into solutions to resolve these issues.

Secure File Copy
Secure Copy, scp, works for Windows. The tests run under Unix have failed.
Secure File Transfer
Secure File Transfer Protocol, sftp, works under Windows and Unix.
- Use passive mode to initiate connections from the client side. Passive mode must be used to download files when you are behind a firewall. To set passive mode for Internet Explorer, navigate Tools | Internet options | Advanced. Then under Browsing, check the box "Use Passive FTP (for firewall and DSL modem compatibility)". If you are using a command prompt, open the sftp session and type

passive

To learn more about passive mode see http://slacksite.com/other/ftp.html.

The default home directory for sftp connections is /. Only one directory is visible, ftproot. To see your own home directory, type

cd ftproot

You can typically configure an sftp client to set the Home folder to /ftproot. For the SSH Secure Shell client, navigate Edit | Settings | Profile Settings | File Transfer | Remote Favorites.

Transferring files using Drag-and-Drop

Note: This method is appropriate if you are located on the Cornell Campus.
You can Cut/Copy/Paste files between your Windows computer and CTC if you map the H: drive and change the DNS settings for TCP/IP (instructions below specifically for XP).

Mapping the network drive H: in Windows

Open My Computer
Click on Tools -> Map Network Drive
Drive H: (if you are already using this drive letter, use another letter)
Folder: \\tc.cornell.edu\tc
Then:
- Select "Connect using a different user name:". This will allow you to enter the domain associated with the CTC and your id at the CTC, rather than those associated with your own machine.
- User name: your_userid@tc.cornell.edu
- Password: your CTC password
Troubleshooting: If you have already mapped the drive and subsequently have problems, disconnect the drive and remap it.

Next, Change the DNS settings for TCP/IP:

Start
Control Panel
Network and Internet Connections
Network Connections
Right click on a connection
Properties
Internet Protocol(TCP/IP)
Properties
Advanced
DNS Tab
Append these DNS suffixes (in order):
Add
tc.cornell.edu
Add

If you have not previously pointed to the CTC WINS Server
- OK
- OK
- Close
If you have pointed to the CTC WINS Server, select the WINS tab.
- 128.84.5.67
- Remove
- OK
- OK
- Close

Mapping the network drive H: in MAC OS X

Use "Connect to server" from the "Go" menu in Finder. Specify smb://tc.cornell.edu/tc/ and hit "Connect". When the authentication form appears, enter the domain CTC_ITH, your username, and your password into the three boxes and click "OK". A new drive appears on your desktop. Open this drive, and the remote Windows files and folders are now accessible inside Mac folders.

If you have problems with an smb connection to //tc.cornell.edu/tc, then make a more specific connection, e.g. smb://ctcfsrv9.tc.cornell.edu/tc_p/. To find the connection for your id, on a ctclogin node, navigate My Computer | Network Drives(tc...) | Users. Then right click on your home folder (i.e. the folder with your username) and left click on properties. Select the DFS tab. In the Path, you will see a ctcfsrv... string similar to the one above. Use that with smb:.

If you have any questions, please send electronic mail to consult or call (607) 254-8686 and press 2 to speak to a consultant.


Home Services Support

Accessing CTC Machines

There are three main ways in which you can get access to CTC login machines and fileservers. These are Remote Desktop Connection, SSH, and Drag-and-Drop Files. Login ID To login to a CTC machine, enter your_userid@tc.cornell.edu as the User name. Remote Desktop Connection (preferred) Login machines This method of connecting to the login machines (winlogin1, winlogin2) is preferred because it provides you with a fully functional Windows desktop. At the login screen, "Log on to" should be CTC_ITH , not the name of the machine to which you are connecting. Batch machines Once you have established a remote desktop connection to a login machine, you can use a remote desktop connection to connect to a batch machine on which you have a running job. You cannot use telnet. These machines provide a command line interface, plus the normal graphical user interface for individual applications. To leave the batch machine, type logoff or shutdown -l at a command prompt. If you use a Windows machine: Use the Remote Desktop Connection (older name Terminal Services Client) to connect to a login machine. This software is pre-installed with Windows XP. To run it, click Start, then All Programs, Accessories, Communications, and Remote Desktop Connection. Otherwise you need to download the client before you can use it. NOTE: If you are a local administrator on your computer and are running Internet Explorer 5 or later, you can use the Remote Desktop Web Connection. This web interface is called TSWeb and can be accessed at http://www.tc.cornell.edu/tsweb. Enter the name of a login machine in the Server box and choose your preferred screen size. If you choose Full Screen you can toggle between your Remote Desktop session and your desktop by hitting Ctrl Alt Pause simultaneously. Hit connect and you will be brought to a Windows login screen, where you can log in as you normally would. If you use Mac OS X v.10.2.8 or later: Use the free download from http://www.microsoft.com/mac/download/misc/RDC.asp. Works just like the Remote Desktop Connection in Windows XP. You can also use rdesktop (see below). If you use Unix or Linux or Mac: You can access the login machines by using the cross-platform rdesktop client. If you are running Linux, typically it is part of the distribution. If you prefer to build it yourself, it is available for download from http://www.rdesktop.org/. Executables are available from http://www.jacco2.dds.nl/rdesktop/index.html. SSH and Friends SSH/telnet You cannot telnet to any CTC machine. This method is insecure. Use SSH to connect to the login machines. SSH cannot be used to connect to the batch machines. If you want to connect to a batch machine, use a Remote Desktop connection to a login machine, then another Remote Desktop connection to a batch machine. sftp/ftp Use sftp for secure file transfers. Since ftp is not secure, it has been disabled as a method to access the login machines for file transfer. SSH Servers The SSH servers are now the login nodes winlogin1.tc.cornell.edu and winlogin2.tc.cornell.edu. Since SSH makes a distinction between winlogin1.tc.cornell.edu and winlogin1, be consistent. To be on the safe side, use the fully qualified server names. These are the only 2 CTC Windows machines to which you can connect with SSH. SSH Clients Must support the SSH2 implementation. For Windows, H:\CTC Tools contains the installation executable SSHWinClient.exe (for ssh2/sftp2/scp2) and puTTY. Instructions on installing SSHWinClient.exe . Details on using the SSH GUI. Other sites from which ssh clients can be downloaded: SSH Secure Shell At this site the file to download is ftp://ftp.ssh.com/pub/ssh/SSHSecureShellClient-3.2.9.exe. Open SSH puTTY Scroll Bars in SSH To obtain a scroll bar in the window can sometimes require settings that are different from the defaults. SSH Secure Shell Edit -> Settings -> Profile Settings -> Connection, set Terminal answerback to tty Keyboard, check Enter sends CR and LF puTTY After invoking puTTY from the command line Connection -> Terminal Type String -> tty Terminal -> check box "Implicit CR in every LF" Windows command line in SSH To get the correct formatting of the screen, set term=tty before issuing "ssh2 winlogin1". It does not yet have file completion and the up/down arrows do not retrieve commands. We are looking into solutions to resolve these issues. Secure File Copy Secure Copy, scp, works for Windows. The tests run under Unix have failed. Secure File Transfer Secure File Transfer Protocol, sftp, works under Windows and Unix. Use passive mode to initiate connections from the client side. Passive mode must be used to download files when you are behind a firewall. To set passive mode for Internet Explorer, navigate Tools \| Internet options \| Advanced. Then under Browsing, check the box "Use Passive FTP (for firewall and DSL modem compatibility)". If you are using a command prompt, open the sftp session and type passive To learn more about passive mode see http://slacksite.com/other/ftp.html. The default home directory for sftp connections is /. Only one directory is visible, ftproot. To see your own home directory, type cd ftproot You can typically configure an sftp client to set the Home folder to /ftproot. For the SSH Secure Shell client, navigate Edit \| Settings \| Profile Settings \| File Transfer \| Remote Favorites. Transferring files using Drag-and-Drop Note: This method is appropriate if you are located on the Cornell Campus. You can Cut/Copy/Paste files between your Windows computer and CTC if you map the H: drive and change the DNS settings for TCP/IP (instructions below specifically for XP). Mapping the network drive H: in Windows Open My Computer Click on Tools -> Map Network Drive Drive H: (if you are already using this drive letter, use another letter) Folder: \\tc.cornell.edu\tc Then: Select "Connect using a different user name:". This will allow you to enter the domain associated with the CTC and your id at the CTC, rather than those associated with your own machine. User name: your_userid@tc.cornell.edu Password: your CTC password Troubleshooting: If you have already mapped the drive and subsequently have problems, disconnect the drive and remap it. Next, Change the DNS settings for TCP/IP: Start Control Panel Network and Internet Connections Network Connections Right click on a connection Properties Internet Protocol(TCP/IP) Properties Advanced DNS Tab Append these DNS suffixes (in order): Add tc.cornell.edu Add If you have not previously pointed to the CTC WINS Server OK OK Close If you have pointed to the CTC WINS Server, select the WINS tab. 128.84.5.67 Remove OK OK Close Mapping the network drive H: in MAC OS X Use "Connect to server" from the "Go" menu in Finder. Specify smb://tc.cornell.edu/tc/ and hit "Connect". When the authentication form appears, enter the domain CTC_ITH, your username, and your password into the three boxes and click "OK". A new drive appears on your desktop. Open this drive, and the remote Windows files and folders are now accessible inside Mac folders. If you have problems with an smb connection to //tc.cornell.edu/tc, then make a more specific connection, e.g. smb://ctcfsrv9.tc.cornell.edu/tc_p/. To find the connection for your id, on a ctclogin node, navigate My Computer \| Network Drives(tc...) \| Users. Then right click on your home folder (i.e. the folder with your username) and left click on properties. Select the DFS tab. In the Path, you will see a ctcfsrv... string similar to the one above. Use that with smb:. If you have any questions, please send electronic mail to consult or call (607) 254-8686 and press 2 to speak to a consultant.



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