Filebeat被配置为使用来自Kafka的输入和到文件的输出
当关闭多行设置时，输出会发布到文件中。但是当Kafka输入配置为mutiline时，文件中没有输出（甚至没有创建文件）
这里是相关的filebeat配置
输入配置

filebeat.inputs:
  - type: kafka
    hosts:
      - <ip>:9092
    topics:
      - "my-multiline-log"
    group_id: "kafka-consumer-filebeat"
    parsers:
      - multiline:
          #          type: pattern
          pattern: '^'
          negate: true
          match: after

字符串
输出配置：

output.file:
  path: "/tmp/filebeat"
  filename: filebeat
#  codec.format:
#    string: '%{[message]}'

型
Filebeat相关日志

2021-12-16T11:02:34.551Z    INFO    [input.kafka]   compat/compat.go:111    Input kafka starting    {"id": "19A7FFEEC9EDFC04"}
2021-12-16T11:02:34.551Z    INFO    [input.kafka.kafka input]   kafka/input.go:129  Starting Kafka input    {"id": "19A7FFEEC9EDFC04", "hosts": ["<ip>:9092"]}
2021-12-16T11:02:38.158Z    DEBUG   [reader_multiline]  multiline/pattern.go:142    Multiline event flushed because timeout reached.
2021-12-16T11:02:44.767Z    DEBUG   [reader_multiline]  multiline/pattern.go:142    Multiline event flushed because timeout reached.
2021-12-16T11:02:51.481Z    DEBUG   [reader_multiline]  multiline/pattern.go:142    Multiline event flushed because timeout reached.
2021-12-16T11:02:58.225Z    DEBUG   [reader_multiline]  multiline/pattern.go:142    Multiline event flushed because timeout reached.
2021-12-16T11:03:04.555Z    DEBUG   cgroup/util.go:276  PID 1 contains a cgroups V2 path (0::/) but no V2 mountpoint was found.
This may be because metricbeat is running inside a container on a hybrid system.
To monitor cgroups V2 processess in this way, mount the unified (V2) hierarchy inside
the container as /sys/fs/cgroup/unified and start metricbeat with --system.hostfs.

型
在日志中重复获取相同的四行reader_multiline
编辑：Kafka的多行解析器支持已在7.16版本中添加