Grok parsing syslog error

Elastic Stack Logstash
3

i removed the grok pattern in the filter conf. Now i only have a small grok in the input conf

input {
  syslog {
      port => 5000
      syslog_field => "syslog"
      grok_pattern => "<%{POSINT:syslog_pri}>"
      tags => "syslog"
      add_field => {
          "origin" => "syslog"
      }
  }
}

Now i´m only getting _grokparsefailure_sysloginput but still no syslog_pri in my log.