On May 7, 2013 10:51 PM, "Matt Wise" <matt@nextdoor.com> wrote:
>
> I've done some more testing and now have narrowed the problem down to our Amazon ELB. Because the OSS version of Syslog-ng does not support failing over destinations from hostA to hostB when one fails, we are using an ELB in front of our syslog servers.
>
> When we have no ELB in place, our syslog-ng client detects the network drop immediately and begins to try to reconnect. When the ELB is in the way, it never detects the network connection drop. I don't understand why. I've tested a bit manually using openssl to connect to our remote endpoint through the ELB and directly and I don't see any difference in the way network connections are killed off. Any thoughts here?
>
Hmm interesting. The difference might be how connections are terminated. Can you check that using tcpdump?
> --matt
>
> On May 6, 2013, at 9:53 AM, Matt Wise <matt@nextdoor.com> wrote:
>
> > We're running Syslog-NG 3.3.4 in our mixed Ubuntu 10/12 environment. We use SSL for all of our syslog-to-syslog connections, and have logging going to two different data pipelines.
> >
> > Data Dest #1: SyslogNG Client ----(SSL)----> SyslogNG Server ------> Logstash File-read-in-service
> > Data Dest #2: SyslogNG Client ----(SSL)----> Stunnel Service ------> Flume Syslog Service
> >
> > The data streams work fine most of the time, but if we restart either the remote syslog-ng server, or the stunnel service, it seems that the syslog ng clients don't try to reconnect for a LONG time (or ever) to the endpoints again. I end up seeing the connection on the client go into a CLOSE_WAIT state, and syslog-ng keeps thinking that its sending log events through the connection, so it seems to never try to reconnect.
> >
> > I've tried setting time_reopen() to 0, 1 and 5... no luck or change in behavior.
> >
> > Any thoughts?
> >
> > --Matt
> >
>
> ______________________________________________________________________________
> Member info: https://lists.balabit.hu/mailman/listinfo/syslog-ng
> Documentation: http://www.balabit.com/support/documentation/?product=syslog-ng
> FAQ: http://www.balabit.com/wiki/syslog-ng-faq
>