Log stash and log stash forwarder how should it be used

Newbie Question
It seems that logstash can send logs to another server that is running elastic search. What is the need for log stash-forwarder? Security?

Setup that I am trying to design.

App Logs Machine              Log Server
log stash send to ->           elasticSearch

or
log-stash-forwarder -          logstash
                               elasticsearch

logstash-forwarder exists primarily because Logstash has a pretty large deployment overhead (both disk space and RAM) which can be a problem for small machines. Quoting the readme file:

Perceived Problems: Some users view logstash releases as "large" or have a generalized fear of Java.

Actual Problems: Logstash, for right now, runs with a footprint that is not friendly to underprovisioned systems such as EC2 micro instances; on other systems it is fine. This project will exist until that is resolved.

Logstash doesn't seem to have all of the same features to send logs via lumberjack as logstash-forwarder?

Logstash has both input and output plugins for the Lumberjack protocol, so what are you missing, specifically?

I've a different problem / question from the the original questioner but for example the output plugin lacks the ability to set fields (type for example) that the logstash-forwarder can do.

In Logstash fields are added by filters, not output plugins. The type field is usually set by input plugins (but can be modified by filters). Logstash is a lot more powerful in this regard.

Yup, as we discussed in my thread, I'm all set at least for now :smile: