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Logstash configuration update - config files, inputs

As a fun addendum to the ELK posts, I'm posting up some of the updated config files in the hopes that it'll help some folk starting down the 'ELK in a Windows environment' path.

Here's our config file structure:

  • 00-inputs.conf (all inputs in here, really just two)
  • 01-filters_start.conf (how I keep the brackets organized)
  • 02-filters_drop.conf (drop stuff first)
  • 10-filters_grok.conf (fixing grokparsefailures to start)
  • 15-filters_mutate.conf
  • 20-filters_tagging.conf
  • 30-filters_metrics.conf
  • 89-filters_end.conf (bracket organization)
  • 90-outputs_start.conf
  • 91-outputs_elasticsearch.conf
  • 92-outputs_nagios.conf
  • 93-outputs_graphite.conf
  • 99-outputs_end.conf

As part of my own self-review, I'll try to go through all of this, but I'll break it up into two posts - one on filters, one on outputs.  The remainder of this post will have config file breakout and Input section discussion.

Config file breakout

Since I'm still a Linux newb, my co-worker kindly informed me that most programs that have a conf.d (config directory) just cat together the contents to build the configuration file.  I found a post (cannot recall where) that showed this basic methodology, so I copied that.  It's working well, means that when I go to edit stuff it's simple, and not pages and pages of code to sift through.

One item I really want to implement is using Git for our Logstash configs - infrastructure as code and all that.  I suspect I'd have to re-point Logstash to the local repo location...something to look into.


input {
    tcp {
        type => eventlog
        port => 1935
        codec => json_lines
    syslog {
        type => syslog
        port => 5514
Pretty simple - NXlog sends to TCP1935, and our syslog intermediary translates standard syslog on port TCP?514 to TCP?5514.  This is done purely because our originating syslog server is really old and gets angry when you try to change the port it's sending on.  Also, you cannot have logstash listen on 514 because that's a restricted port and I'm not fancy enough to make that work.  (it might not even be a good idea to force it)

Next post, Filters...


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