Changing logstash @timestamp timezone

Hi,

I am new to logstash and playing around with it. I have a simple set-up in which I am forwarding logs using logstash-forwarder to logstash. Both logstash and logstash-forwarder are in the same machine.

My logstash config file is as below:-

input {
 lumberjack {
  port => 6782
  ssl_certificate => "/home/d/Documents/logstash/ssl_key/logstash-forwarder.crt"
  ssl_key => "/home/d/Documents/logstash/ssl_key/logstash-forwarder.key"
  type => "lumberjack"   
 }
}

filter {
  if [message] =~ /^\s*$/ {
        drop { }
  }  
}

output { 
 stdout { codec => rubydebug } 
}

My logststash-forwarder is like below:-

{
    "network": {
        "servers": [ "localhost:6782" ],
        "ssl ca": "/home/d/Documents/logstash/ssl_key/logstash-forwarder.crt",    
        "ssl key" : "/home/d/Documents/logstash/ssl_key/logstash-forwarder.key",
        "timeout": 15
    },
    "files": [
        {            
            "paths": [ "-" ],
            "fields": { 
                "type": "stdin",
                "app" : "test"
            }
        }
    ]
}

When I enter a simple Hello in the logstash-forwarder stdin.

Hello
2015/07/16 15:22:25.426913 Registrar: processing 1 events

I get the below output in logstash console:-

{
       "message" => "Hello",
      "@version" => "1",
    "@timestamp" => "2015-07-16T09:52:25.425Z",
          "type" => "stdin",
          "file" => "-",
          "host" => "d-1383",
        "offset" => "13",
           "app" => "test"
}

When I execute date in the machine in which the logstash and logstash-forwarder is installed it produces the below output

Thu Jul 16 15:22:46 IST 2015

Can someone let me know how can I make @timestamp equal to the same timezone in which the event was generated? How can I make logstash make use local timezone of the machine in which it is running?

The @timestamp field is UTC by definition. Display layers, like Kibana, should adjust this to local timezones where necessary.