Docs report that `time_file` and `size_file` are optional, but you need to **at least** set one of those to make this work: ``` output { s3{ access_key_id => "crazy_key" (required) secret_access_key => "monkey_access_key" (required) endpoint_region => "eu-west-1" (required) bucket => "boss_please_open_your_bucket" (required) size_file => 2048 (optional) time_file => 5 (optional) format => "plain" (optional) canned_acl => "private" (optional. Options are "private", "public_read", "public_read_write", "authenticated_read". Defaults to "private" ) } ``` CC @palecur @debadair