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<div>Hi,</div>
<div><br>
</div>
<div>we are in the middle of an investigation of a partial-write issue and found a bug that can lead to message loss in some circumstances, even when reliable diskbuffer is used.</div>
<div>We marked this bug as release critical. Fortunately we fixed the issue a few minutes ago, so we are going to release 3.17.2 that contains the fix ( https://github.com/balabit/syslog-ng/pull/2224 ).</div>
<div><br>
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<div><br>
</div>
<div>We don't have an automated testcase for this, actually it is in progress(this is why we didn't catch the bug), but sharing the manual reproduction:</div>
<div><br>
</div>
<div>* listen with netcat (and use pv tool to make partial write happen)</div>
<div> nc -l 61002 | pv -L 40</div>
<div>* run syslog-ng with the following config:</div>
<div>@version: 3.17</div>
<div>options {</div>
<div> time_reopen(3);</div>
<div> stats_level(1);</div>
<div>};</div>
<div>source s_network {</div>
<div> network(ip("127.0.0.1")</div>
<div> port(5555));</div>
<div>};</div>
<div><br>
</div>
<div>destination d_network {</div>
<div> network("127.0.0.1" disk_buffer(mem-buf-size(1000) disk-buf-size(1048576) reliable(yes) dir('/tmp/dq'))</div>
<div> ip_protocol(4)</div>
<div> port(6666)</div>
<div> so-sndbuf(4096));</div>
<div>};</div>
<div><br>
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<div>log {</div>
<div> source(s_network);</div>
<div> destination(d_network);</div>
<div><br>
</div>
<div> flags(flow-control);</div>
<div>};</div>
<div><br>
</div>
<div>* send logs</div>
<div> loggen -r 100000 -I 200 127.0.0.1 10001 --inet</div>
<div><br>
</div>
<div>* wait a few seconds then stop netcat</div>
<div><br>
</div>
<div>* result: syslog-ng will drops all the incoming messages</div>
<div><br>
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<div><br>
</div>
<div>regards,</div>
<div>Laszlo Budai</div>
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