Executing File Transfers

This topic provides detailed information on what happens when File Transfers are executed.

This page includes the following:

Overview

Converting Character Sets

Exchanging data between different system platforms requires the character sets to be converted. This is done automatically using the Code Tables (CODE). The transfer can be structured, thus enabling the exchange of files with packed and binary fields in heterogeneous system environments. All network transfers are encoded by default.

Agent Connection

For each file transfer, a separate connection is established between the Agents. Agents for the OS/400, Windows, Unix, z/OS and NSK operating systems handle File Transfers through extra threads. When a File Transfer has ended, the corresponding connection is automatically closed. If there are still open and unused connections, they are closed after the period of time that is defined in the FT_CONNECTION_TIMEOUT key (variable UC_HOSTCHAR_DEFAULT, see UC_HOSTCHAR_DEFAULT - Host Characteristics).

The old file transfer protocol is used if one or both of the affected Agents use Automation Engine version 8.00A or earlier. In this case, only one connection is established between the agents for all File Transfers. The system checks if a connection has already been established between the two Agents before a File Transfer starts. If so, this connection is used and no attempt is made to establish a separate connection. After the File Transfer has ended, the system ensures that a connection that is still used is not closed.

Notes:

Transferring Files

Each File Transfer stars by establishing a connection between the source and the destination. There are two methods of transferring files:

Notes:

Advantage of Temporary Files

Temporary Files on the File Structure of the Source Agent

Each time a source Agent does a File Transfer, it creates two temporary files:

The location of these files is defined by the UC_EX_PATH_JOBREPORT variable set in the [VARIABLES] section of the Agent INI configuration file.

The Agent uses these files to reconstruct the File Transfer if the Agent is restarted or if a transfer fails. If the File Transfer completes successfully, the files are automatically deleted. If the File Transfer fails to make a restart, the files remain on the file system. The number of days the status files remain is defined by the value of the FT_RESTARTINFO_LIFETIME key in the UC_HOSTCHAR_DEFAULT variable.

For more information, see List of Agent Variables and UC_HOSTCHAR_DEFAULT - Host Characteristics.

Agent Groups in File Transfers

In a File Transfer it is possible to select an Agent Group either as source or as target. It is not possible to select an Agent Group in both. This results in the following two scenarios:

End Status

Transferring a Particular File

A File Transfer has the status ENDED_NOT_OK if the relevant file is not available.

Transferring Files Using Wildcard Characters

A File Transfer hast the status ENDED_EMPTY if no file is available that complies with the filter specifications. It has the status ENDED_OK if at least one matching file is found.

UNIX

For security reasons, it is recommendable that the login_check=yes parameter is set to yes in the INI file of the UNIX Agent. With this setting, the password specified in the login object assigned to the File Transfer is checked. If login_check=no is set, only the user name is checked.

VMS

In VMS, each text file requires that a delimiter is appended. The FileEndDelimiter= parameter in the INI File determines whether the VMS Agent should append one. For more information, see Agent VMS.

See also: