Using FTP

Revision Date: 8/13/2003. E. Kleban

Generic material on FTP.

Reference material on FTP.

The FTP command on the IBM mainframe works according to the rules in the "generic" material above. The program itself resides on a disk called TCP so those who don't use the mainframe's menus must first type in: SHARE TCP before entering the FTP command. (Menu users do not need to do this.)

FTP from elsewhere TO the mainframe is also feasible, and works normally except that older accounts on the mainframe impose a second level of password protection. Newer mainframe accounts do not need to go through this procedure.

The person with an older account wishing to permit FTP access to their mainframe disk space must first create a read/write disk password. The mainframe command to do this is: 

  DIRM MD

In the resulting screen, type the id number of the disk you want to have the password. For your A disk the id number is 191. Then tab to the password fields. Enter the same password for both the read and write fields but please do not use the "multi" field. The password you enter for the read and write fields must be different from your normal logon password, but must follow the same rules (6-8 letters or numbers). Press return or enter when you have typed in the passwords. You will be asked to prove your identity by typing in your logon password.

Once you have set your disk password, you can logoff and use FTP from some other Internet computer to access your mainframe files. When you use FTP on some other computer, you enter your normal logon id and password when first connecting to the mainframe. Then you must use the command: 

  cwd xxxx.191

where "xxxx" is your mainframe logon id and 191 is your mainframe A disk (for which you have set the disk password). You can also set passwords and connect to other mainframe disks you may own.

To enter the disk password you must use the ACCOUNT command in FTP. This command must be in a format that is "understood" by both the local FTP program and the mainframe. The format varies somewhat from program to program. The basic command is: 

  ACCOUNT yyyyy

where "yyyyy" is the disk password.

The distributed programs WS-FTP (for MS Windows) and Fetch (for Macintosh) that UNET supports for FTP on those platforms both permit easy entry of the account password in a special field. Each program can detect that they are connecting to an IBM mainframe running CMS and will correctly handle the secondary password. You will still have to tell them to use directory xxxxx.191 however.

Note: If you are logged on to your mainframe account you cannot gain write access to your mainframe disks using FTP from another computer. So you must logoff before using FTP.