Pipeline aborted due to error

My logstash service status change into "Active (Exited)" after few seconds of starting the service.
I got a logstash error as follows in the logstash.log

{:timestamp=>"2016-10-10T11:11:04.510000+0530", :message=>"stopping pipeline", :id=>"main"}
{:timestamp=>"2016-10-10T11:33:10.283000+0530", :message=>"Pipeline aborted due to error", :exception=>"LogStash::ConfigurationError", :backtrace=>["/opt/logstash/vendor/bundle/jruby/1.9/gems/logstash-core-2.4.0-java/lib/logstash/config/mixin.rb:88:in config_init'", "org/jruby/RubyHash.java:1342:ineach'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/logstash-core-2.4.0-java/lib/logstash/config/mixin.rb:72:in config_init'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/logstash-core-2.4.0-java/lib/logstash/outputs/base.rb:79:ininitialize'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/logstash-core-2.4.0-java/lib/logstash/output_delegator.rb:74:in register'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/logstash-core-2.4.0-java/lib/logstash/pipeline.rb:181:instart_workers'", "org/jruby/RubyArray.java:1613:in each'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/logstash-core-2.4.0-java/lib/logstash/pipeline.rb:181:instart_workers'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/logstash-core-2.4.0-java/lib/logstash/pipeline.rb:136:in run'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/logstash-core-2.4.0-java/lib/logstash/agent.rb:491:instart_pipeline'"], :level=>:error}

and my conf file as follows

input {
lumberjack {
port => 5000
type => "logs"
ssl_certificate => "/etc/pki/tls/certs/logstash-forwarder.crt"
ssl_key => "/etc/pki/tls/private/logstash-forwarder.key"
}
}

filter {
if [type] == "syslog" {
grok {
match => { "message" => "%{SYSLOGTIMESTAMP:syslog_timestamp} %{SYSLOGHOST:syslog_hostname} %{DATA:syslog_program}(?:[%{POSINT:syslog_pid}])?: %{GREEDYDATA:syslog_message}" }
add_field => [ "received_at", "%{@timestamp}" ]
add_field => [ "received_from", "%{host}" ]
}
syslog_pri {}
date {
match => [ "syslog_timestamp", "MMM dd HH:mm:ss", "MMM dd HH:mm:ss" ]
}
}
}

output {
elasticsearch host => ["localhost"]
stdout { codec => rubydebug }
}

what could be the issue??

elasticsearch host => ["localhost"]

elasticsearch { hosts => ["localhost"] }

ah finally hosts is the problem typo
Its working now thank you