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ISSUE: [ChunkedOutputStream.FlushData.execute Failed to flush buffer to this destination

Article ID: 5231
Reviewed: 02/03/2017

Product Version:
AhsayOBM / AhsayACB: or above
OS: All platforms

Problem Description

When performing a backup job of any type, the following error is receieved in the backup log:

No. Type Timestamp Log
* ... ... ...
* info ... ...
* erro YYYY/MM/DD hh:mm:ss Error="ChunkedOutputStream.FlushData.execute] Failed to flush buffer (directory_path\vm_name-flat.vmdk)
to this destination. Error=' [FastPipedOutputStream.write]FastPipedOutputStream has
been closed by the reading thread.', caused by [IOException][FastPipedOutputStream.write]
FastPipedOutputStream has been closed by the reading thread."
* ... ... ...


This issue is caused by an unstable network connection between the AhsayOBM / ACB client machine and the backup destination (e.g. AhsayCBS server or Cloud storage service).


Please try tuning the timeout and retry parameters on AhsayOBM / ACB to workaround the unstable network connection issue.  Increase the number of retry and or read timeout value, this can be done by editing the ${OBC_Install_Home}\afc.opt file.

Parameter Description:


    The number of times AhsayOBM / ACB would retry to send a block to the backup destination. The default value for retry 10 times.


    The read timeout interval before AhsayOBM / ACB retry to send a block to the backup destination. The default timeout value is 90 minutes.


    The default maximum sleep interval value is 16 minutes.

    If the data block upload fails, then AhsayOBM / ACB will sleep for (30 sec) x 2 ^ (no. of retry - 1) minutes and then try to re-upload the data block again, the maximum sleeping interval is 16 minutes (e.g. 960 seconds), for example 30 sec, 60 sec, 120 sec, 240 sec, 480 sec, 960 sec, 960 sec, 960 sec, 960 sec, 960 sec ... etc).
On the AhsayOBM / ACB client computer:

  1. Browse to the ${OBC_Install_Home} folder.
  2. Edit the afc.opt file.
  3. Add the following values to the afc.opt file.

    Recommended values:

  4. Save the file
  5. Run the backup job again.


Retry, timeout, network, sleep, network, ChunkedOutputStream.FlushData

public/5231_issue/chunkedoutputstream.flushdata.execute_failed_to_flush_buffer_to_this_destination_error.txt · Last modified: 2020/10/30 11:27 by edward.chan