Recently while configuring a logstash pipeline,I’ve been through an error that was a bit tricky to find since it was referring to a missing plugin named ‘else’.

Searching the issue a bit didn’t  show much help, So I hope this saves couple hours/minutes trying to find out the root cause.
Here’s an interesting part from the Exception Message

The given configuration is invalid. Reason: Couldn’t find any filter plugin named ‘else’…