Auto Resend

If an error such as a network-related error (communication error) occurs during file transfer, or if a forced stop due to a failover occurs on the host on the receiving side (HULFT for UNIX/Linux or HULFT for Windows), HULFT automatically carries out resending. When an error occurs during transfer, HULFT can transfer data from the point where the error occurred (the Checkpoint Resend File function) when carrying out resending.

(1) Flow of Auto Resending

The flow of auto resending is illustrated in Figure 2.8 .

Figure 2.8 Auto Resending

1) Carrying out of Send processing

The Send program (XRSND) transfers the data of the Send work file or the Send file to the remote host according to the information in the record in the Resend Queue.

2) Occurrence of communication error or failover on receiving host

If an error occurs somewhere along the communication line during file transfer, or if a forced stop due to failover occurs on a host on the receiving side that is one of the following host types, the Send program (XRSND) detects the error and discontinues the processing:

HULFT for UNIX/Linux
HULFT for Windows

3) Writing of Send Log record and startup of Post-send Job

The Send program (XRSND) writes the result of the communication error to the Send and Receive Log file (HULFT.LOG), and starts Post-send Jobs that are registered as unsuccessful jobs.

4) Carrying out of auto resending

After waiting for the specified time, the Send program (XRSND) automatically repeats 1) to 3) the set number of times. The program repeats 1) to 3) only when an error occurs in 2) .

5) Writing of record in Send Queue

If the Send processing ends unsuccessfully, the Send program (XRSND) writes the information of the transfer that terminated unsuccessfully (the record in the Resend Queue) to the Send Control file (HULFT.QUEUE).

= Remarks =

By executing the Resend File program (XRRSNDGO), you can manually carry out resending for the records that are written to the Send Control file (HULFT.QUEUE).
When a communication error occurs in 2) , the host on the receiving side terminates with a communication error. HULFT carries out auto resending on the host on the sending side. When the host on the receiving side and the host on the sending side reconnect, the Receive processing will be carried out.

(2) Error Codes that Signify that HULFT Will Carry Out Auto Resending

The following error codes of the Send processing signify that HULFT will carry out auto resending for the attempt:

Table 2.1 List of Error Codes that Signify that HULFT Will Carry Out Auto Resending
Status Code	Detail Code	Error Message
8	2	An error occurred during transfer processing.
8	3	An error occurred during receiving.
16	535	An error occurred on the host on the receiving side. For details about messages, refer to Error Codes and Messages for the host type of the host on the receiving side.
16	591