# Common properties and action buttons
| Property | Description |
| --- | --- |
| Target | 3-character code that serves as the unique identifier of the target
in a given environment. |
| Distribution | 3-character code that serves as the unique identifier of the
distribution. |
| Trace | This property activates traces on the distribution.
To view the resulting file, see Trace button
in the Action buttons table. |
| Hold | This parameter is used to "hold" or inhibit the start of the
distribution for the selected target, until the check box is
unselected. |
| Cache size | This parameter deals with the size of packets sent from the source
engine to the target engine.
Information noteNote: A packet contains whole records.
No record is split between two packets.
To optimize
the communication between the source and target engines, it is
possible to edit the size of the exchange cache (set by default
32KB) in the properties of each distribution. It can be up to 8MB on
AS/400 IBMi platforms, and 128MB in case of other sources.
This feature is
especially useful to increase performances when working with
long-distance communications, especially in case of limited
bandwidth and high-latency networks. |
| Action button | Description |
| --- | --- |
| Test | Use this button to test the connection.
If an error message is
displayed, check the connection details. For more information,
see [Configuring target engines
during distribution](https://help.qlik.com/talend/r/en-US/7.3/change-data-capture-user-guide/configuring-target-engines-during-the-distribution). |
| Trace | The Trace button is shown only if
Talend Change Data Capture has detected the presence of a trace file on the
target.
Click this button to download the contents of the
file.
Information noteNote: The trace file contents are overwritten only by the
contents of a new trace. |
| Modify | Use this button to save parameters when you are finished editing
them. |
| Cancel | Use this button to cancel the modifications you have
made. |