The messages are centralized in a message queue on the AS/400 IBMi (DD_USRDATA/DDMSGQ), and in a text file on NT (sub-directory data\DDMSGQ.ddm). The target engines write and send their messages to the source engine which also writes messages.
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You can use the Manager to view the messages or read them directly:
- on AS/400 IBMi, using the DSPMSG DD_USRDATA/DDMSGQ command.
- on Windows NT Server, by opening the data\DDMSGQ.ddm file in MFC WordPad (do not use Notepad as it does not recognize line skips).
To clean up messages, click Clear message queue in the
Manager. It empties the message queue on the source. You can also clear it
manually on AS/400 IBMi using the CLRMSGQ command (DD_USRDATA/DDMSGQ) and on NT
by deleting the data\DDMSGQ.ddm file. On NT, a parameter specifies the maximum
size in kilobytes beyond which the file is cleared automatically (see
Warning: Based on the AS/400 IBMi system setup, when the message queue is full (64MB), it may obstruct source and target startup. You must clean it regularly. We recommend you use scheduler (WRKJOBSCDE) to clean it Monday through Friday before you leave in the evening, so that messages generated during the night are kept. Since the message queue in AS/400 IBMi is not linked to a user profile, it is not included in the cleanup tasks.