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Logging into the Statistics Network from Offsite and File Transfering

PC and Unix connectivity

File transfer, access and login sessions

There are three ways in which one can connect a PC to the Statistics Unix systems–and to other systems that accept the same communication protocols and are reachable by the network. Two are by running either WinSCP and/or TTSSH and the third one by directly mounting your Unix files making look like a driver in the PC. Each one of these procedures suit different working needs and environments, which we will describe below.

TTSSH

TTSSH allows you to create a login session in another computer that runs the SSH protocol. SSH stands for “secure shell”.

TTSSH can be downloaded here.

A pointer to the TTSSH software is usually in the desktop, but if not, the program can be find in:

C:\Program Files\TTERMPRO\

Although TTSSH gives a login connection to Unix, by creating a window that looks like a window terminal, TTSSH does not provide other windows facilities. You can execute Unix commands at the terminal, such as list your files or use a simple editor as pico or basic email agents such as pine or mutt, but you can not run X Window System applications such as Mozilla. To use TTSSH do as following:

  1. Double click the shortcut or executable to open the application.
  2. You will be given a choice of a few lab machines where you can log in. You can select one of them or type the name of the machine you want to connect to. (Generally you will do the latter when you want to connect to a machine that is not in the Statistics network. Since all the Statistics machines will look and act the same, it shouldn't matter which one you select.)
  3. If you select one of the listed machines that machine should already be included in the SSH authentication file. If not, or for a machine outside our network, you will see a ‘Security Warning' message. Just click ‘Continue'.
  4. Login information will be requested. Type your user name and password and the connection will be established.
  5. When you are done with the work make sure to log out. Either type the ‘exit' command at the window, or close the window by clicking the ‘x' in the upper right corner, or select ‘Exit' or ‘Disconnect' from the ‘File' menu.

With exception of a few directives such as ‘File|Print', ‘Control|Reset Terminal' and ‘Set Up|Font' and ‘Set Up|Size' (terminal size)– which will apply only to your current session–no other options will be of much use to you. The ‘File|Send File' option, for example, will let you select one file in the PC to send as input to your terminal, not to your file space in Unix, as one may assume. You can use this option, for example, if you are running an editor in your terminal and you want to direct the contains of the file to the editor as input, but there are better ways to transfer files, like either ‘cut and paste' for small text files and a file transfer protocol such as WinSCP for larger files, images or binaries. In addition, WinSCP works by far better than the ‘File|Transfer' option.

Another alternative, however, is to use the remote file copy unix command ‘scp' from the TTSSH terminal as one will do among two Unix systems. Providing the file is on your home directory, type:

scp your_account_name@ssh.stat.umn.edu:file_name.type ./file_name.type

There are also options for the security level of SSH to use but the default (2) is compatible with the Statistics Unix systems and in general will suit most systems.

WinSCP

WinSCP allows you to move files back and forth the PC and your Unix directories. WinSCP has a very flexible and easy to use interface to copy, rename and delete files as well. Unfortunatly, because of this, it can be easy to make a quick mistake and delete some valuable Unix files unintentionally. For some protection against that it may be a good idea to have a Unix folder dedicated to file transfers.

WinSCP can be downloaded here.

A pointer to the WinSC software is usually in the desktop, but if not, the program can be find in:

C:\Program Files\WinSCP2.exe

To use WinSCP do as following:

  1. Double click the shortcut or executable to open the application.
  2. You will be given the option to connect to ssh.stat.umn.edu. This is the machine designated to handle file transfers in the Statistics network. Double click this option or type another machine name if you want to access a machine on a different network.
  3. If you select one of the listed machines that machine should already be included in the SSH authentication file. If not, you will see a “Security Warning” message. Just click “Continue”.
  4. Login information will be requested. Type your Department username and password and the connection will be established.
  5. A window will open with information on a selected folder of PC files on the left and on files on the target machine on the right. You can move up and down to other folders following either one of those paths.

You can drag files and folders back and forth the PC (from the Desktop or any other open folders) and the target machine and/or you can select a file or folder on either one and implement one of the action options listed at the button of the window: Remove, Copy, Move or Delete. – Dragging a file is equivalent to the Copy option.

The Copy option will give you additional choices from the ‘More' button. There you can select the transfer mode which is ‘Automatic' by default but it can be set to Binary or Text. You can also select the protection type that the file to be copied will have in the target system. The default protection is read and write mode by the owner and read mode by anyone else. You may want to reset that for sensitive files that should not be visible to others. Please note that the protection goes back to the default value for each transfer operation, so you either will have to keep resetting it or login to Unix when you are done with the transfer and change all the values at once.

When you are done with the transfer session make sure to close the transfer window, either by clicking on ‘x' on the the upper right corner or use the ‘Disconect' option from the ‘Session' menu. If you do not close the window any one who uses the PC after you will have full access to your Unix files.

Empty the Recycle Bin to permanetly get ride of deleted files from the PCs disks. This does not appply to the files deleted in Unix that are permanetly removed when you select to delete them, as if you would had used the ‘rm' command.

Mapping Unix space as a drive

You can mount your Unix home directory or any subdirectory on the PC by “mapping” it to a PC drive and therefore making it to look like another drive on the PC. You can use this type of connection to transfer files just by dragging the file icons back and forth between the PC's space and the temporary mounted drive. The dragging option will work like a copy operation: files will not be moved but just duplicated.

This is an easy way to transfer files but does not allow the choices for mode and permissions that are available with WinSSP. This is advantageous when you work with some applications that may build data pointers based on file structure, since just dragging the files will not suffice to update the structure. With the mapping, the PC application will place and remove files within the requirements of its own structure and maintain the pointers.

To ‘map' a Unix directory or subdirectory to a PC drive proceed as following:

  1. Open “My Computer” by double clicking on it.
  2. Select ‘Map Network Drive' from the ‘Tools' pull down menu at the top of the window.
  3. Select any free drive such as B:, G:, H:, etc.
  4. Type the ‘folder' info as: \\stat.umn.edu\username – for your home directory or \\stat.umn.edu\username\subdirectory – for a subdirectory
    (Hint: see list from the ‘Browse' option for the format. Also, see the Note below)
  5. You will see a message telling you that you are using an incorrect username and be requested to type your Unix user name and password.
  6. Type your user name and password and the drive will be connected.

When you are done working with this file space dismount the drive. The ‘Dismount' option is also in the ‘Tools' menu. If the drive is not dismounted, then any one using the PC after you will have full access (read, write, remove) to your files.

As we said before for file transfers with WinSCP, to avoid possible mistakes it is a good idea to have a Unix subdirectory dedicated to the files that you will use in the PC and to map just that folder to a PC drive.

Note: Once you mounted a drive that drive will be remain listed among the choices for mounting from the ‘Browse' option. Any one with an account in the Unix system will be able to mount that file space. This is no different than any user on the Unix systems being able to see ('cd' into) your file space. As when working in the Unix systems, others will be able to see the files that are not read protected but in general they will not be able to make changes to them. (For others to write or delete your files you have to previously set up permissions as such.)