How to use "DAY" Grok Pattern on Filebeat Multiline

Hi.

I'm use the next configuration to read a multiline file on logstash. For identify the begin of the message I use a grok pattern

 file {
        path => "Sample_Type1/*"
        start_position => "beginning"
        type => "alertlog_type1"
        codec => multiline {
            **pattern => "^%{DAY}"**
            negate => "true"
            what => "previous"
            max_lines => 100000
        }
    }

But, when I'm try to use the same configuration on Filebeat this not work.

Any idea for this?

Thanks.

I don't think u can use a grok pattern for multiline in filebeat. You'll need to just copy the regex that it uses directly.