Extract concrete words with logstash

Hi!
I was interested in knowing if with logstash I could find words that match a pattern and extract them from the message, without parsing the whole message.

For example:

there has been an error on the **s123s** machine due to a blackout.

would like from this message to keep the name of the machine when it meet a pre defined pattern but the text is random because is an email so i cant parse the rest of the message because its not static as a log.

Thanks in advance!!

You can use grok to match a message against a regexp. There is no need to match the entire message.

thank you!! it finally works.

my example :

there has been an error on the s97bbdd001 machine due to a blackout

my regular expression: (?[a-zA-Z]\d.{1}....\d.{2})

[
  {
    "server": "s97bbdd001"
  }
]