Service request/response expressions

Hello all,

For me it's not clear what to fill in for the Service request/response
fields.
From the forum I’ve got an example for an http service check.

Service type HTTP
Request: www.foo.bar:/index.html
Response: ^HTTP/1\.[01] 200.*

This works fine, but i don't know what to fill in for example an SMTP
service check.

Is there any documentation for the use of these fields? (Regular
expressions etc.)

I can't find anything in the current documentation or forums.

Many thanks in advance for your reply.

Greetings,

Joop Martens
The Netherlands

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