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<p class="MsoNormal">I have a pair of syslog-ng OSE servers on different LANs, which forward some of the log entries that they receive to separate collectors. In other words,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"> Syslog-A -> collector-A<o:p></o:p></p>
<p class="MsoNormal"> Syslog-B -> collector-B<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I would like for the two syslog servers to use a common syslog-ng.conf for obvious reasons. I first built destination clauses with the separate IPs, like so:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console"">destination d_collector {<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""> udp(<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""> "192.168.1.23"<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""> port(514)<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""> template("${DATE} ${HOST} ${MSG}")<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""> );<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console"">};<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">This worked fine. But when I define an environment variable, COLLECTOR_IP, and then change my configuration to:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console"">destination d_collector {<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""> udp(<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""> "`COLLECTOR_IP`"<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""> port(514)<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""> template("${DATE} ${HOST} ${MSG}")<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""> );<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console"">};<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Then syslog-ng’s throughput slows down to a trickle (but does continue); CPU utilization (ordinarily substantial – this is a busy log handler) drops to near zero. Changing the configurations back to use the raw IP address restored previous
throughput. There are no unusual messages in syslog-ng’s own logfile.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Anyone seen this puzzling behavior?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks,<o:p></o:p></p>
<p class="MsoNormal">Jon Wilson<o:p></o:p></p>
<p class="MsoNormal"><a href="mailto:jonathan.wilson@vumc.org">jonathan.wilson@vumc.org</a><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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