Getting Data In

Forwarders fail to make connection to server

misschatter
Engager

Frequently, our lightweight forwarders cannot connect to the Splunk server to send log tail output and we end up missing/losing those logs because they roll frequently. The client/forwarder will just log:

06-21-2010 16:24:36.454 WARN  TcpOutputProc - Failed to make a connection, will retry.
06-21-2010 16:24:56.495 INFO  TcpOutputProc - Retrying connection to X.X.X.X:7080...
06-21-2010 16:24:56.496 WARN  TcpOutputProc - Failed to make a connection, will retry.

If I restart the splunk server, then it starts receiving data again. I've already set it up to restart twice a day, but that is not enough.

The Splunk (4.1.3) server is Solaris 11 and a netstat -iv shows it has about 1-2 ierrs every 10 seconds, although the network folks say the switch port shows clean. I've attempted to tune TCP on the server, but it's made no difference.

Also, when it stops receiving data, it will have a screen full of connections to localhost on the mgmt port shown in CLOSE_WAIT state similar to this:

localhost.57325      localhost.8089       32768      0 32768      0 CLOSE_WAIT
localhost.8089       localhost.57325      32768      0 32768      0 FIN_WAIT_2
localhost.33575      localhost.8089       32768      0 32768      0 CLOSE_WAIT
localhost.8089       localhost.33575      32768      0 32768      0 FIN_WAIT_2
localhost.63480      localhost.8089       32768      0 32768      0 CLOSE_WAIT
localhost.8089       localhost.63480      32768      0 32768      0 FIN_WAIT_2

Any ideas? Thanks!

nate015
Explorer

Make sure you don't have an outputs.conf in your app directory ($SPLUNK_HOME/etc/apps/...) that has a tcpoutput to itself.

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