Start logstash error

Elastic Stack Logstash
1

I have configured the logstash.yml configuration file
logstash.yml：

input {stdin{}} output {stdout{}}

But when I enter ./logstash to start, the following error occurs

[2023-07-12T01:16:59,926][INFO ][logstash.runner          ] Starting Logstash {"logstash.version"=>"8.6.0", "jruby.version"=>"jruby 9.3.8.0 (2.6.8) 2022-09-13 98d69c9461 OpenJDK 64-Bit Server VM 17.0.5+8 on 17.0.5+8 +indy +jit [x86_64-linux]"}
[2023-07-12T01:16:59,930][INFO ][logstash.runner          ] JVM bootstrap flags: [-Xms1g, -Xmx1g, -Djava.awt.headless=true, -Dfile.encoding=UTF-8, -Djruby.compile.invokedynamic=true, -XX:+HeapDumpOnOutOfMemoryError, -Djava.security.egd=file:/dev/urandom, -Dlog4j2.isThreadContextMapInheritable=true, -Djruby.regexp.interruptible=true, -Djdk.io.File.enableADS=true, --add-exports=jdk.compiler/com.sun.tools.javac.api=ALL-UNNAMED, --add-exports=jdk.compiler/com.sun.tools.javac.file=ALL-UNNAMED, --add-exports=jdk.compiler/com.sun.tools.javac.parser=ALL-UNNAMED, --add-exports=jdk.compiler/com.sun.tools.javac.tree=ALL-UNNAMED, --add-exports=jdk.compiler/com.sun.tools.javac.util=ALL-UNNAMED, --add-opens=java.base/java.security=ALL-UNNAMED, --add-opens=java.base/java.io=ALL-UNNAMED, --add-opens=java.base/java.nio.channels=ALL-UNNAMED, --add-opens=java.base/sun.nio.ch=ALL-UNNAMED, --add-opens=java.management/sun.management=ALL-UNNAMED]
Your settings are invalid. Reason: Setting "" doesn't exist. Please check if you haven't made a typo.
[2023-07-12T01:16:59,949][FATAL][org.logstash.Logstash    ] Logstash stopped processing because of an error: (SystemExit) exit
org.jruby.exceptions.SystemExit: (SystemExit) exit
        at org.jruby.RubyKernel.exit(org/jruby/RubyKernel.java:790) ~[jruby.jar:?]
        at org.jruby.RubyKernel.exit(org/jruby/RubyKernel.java:753) ~[jruby.jar:?]
        at home.cetc.logstash_minus_8_dot_6_dot_0.lib.bootstrap.environment.<main>(/home/cetc/logstash-8.6.0/lib/bootstrap/environment.rb:91) ~[?:?]

I am puzzled. I cleared logstash.yml and used the command ./logstash -e ‘input {stdin{}} output {stdout{}}’, but it started successfully.

[2023-07-12T01:19:26,074][INFO ][logstash.javapipeline    ][main] Pipeline Java execution initialization time {"seconds"=>0.92}
[2023-07-12T01:19:26,108][INFO ][logstash.javapipeline    ][main] Pipeline started {"pipeline.id"=>"main"}
[2023-07-12T01:19:26,122][INFO ][logstash.agent           ] Pipelines running {:count=>1, :running_pipelines=>[:main], :non_running_pipelines=>[]}
The stdin plugin is now waiting for input:
1
{
       "message" => "1",
    "@timestamp" => 2023-07-11T17:19:31.424360581Z,
         "event" => {
        "original" => "1"
    },
          "host" => {
        "hostname" => "cetc-virtual-machine"
    },
      "@version" => "1"
}
2

The input/filter/output configuration should not be in logstash.yml, it should be in a file pointed to by path.config. You can set path.config in logstash.yml, or on the command line using -f.

3

What i do is usually:

Inside my_logstash_pipeline.conf:

input {stdin{}} output {stdout{}}

Then i go to etc/logstash (the same level with config) and start it.

./bin/logstash -f my_logstash_pipeline.conf

Make sure that there is no logstash running: sudo systemctl status logstash

You can define multiple pipelines in pipeline.yml file. Then start logstash automatically with: sudo systemctl start logstash

Or sudo systemctl restart logstash
Or sudo systemctl stop logstash