# Detection Rules Triggered although ports are closed!

**URL:** <https://discuss.elastic.co/t/detection-rules-triggered-although-ports-are-closed/266533>\
**Category:** Elastic Security\
**Created:** [March 8, 2021, 10:28am UTC](https://discuss.elastic.co/t/detection-rules-triggered-although-ports-are-closed/266533 "2021-03-08T10:28:31Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![ethical20](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/ethical20/32/68123_2.png) [@ethical20](https://discuss.elastic.co/u/ethical20)\
**Post date:** [March 8, 2021, 10:28am UTC](https://discuss.elastic.co/t/detection-rules-triggered-although-ports-are-closed/266533/1 "2021-03-08T10:28:31Z")

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Hi,

In SEIM, I can see some detection rules are triggered like although the related ports are already closed:

`signal.rule.name: "Telnet Port Activity"` (which works on port 23)

and

`signal.rule.name: "SMTP on Port 26/TCP" ` (which works on port 26)

I tried to netcat them and they are triggered again although they are closed!

1- Why the rules are triggered although ports are closed?  
2- how can I disable alerting on closed ports and keep it for open ones only?

Thanks in advance.

Regards,

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<div class="post-metadata">

**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\
**Post date:** [April 5, 2021, 10:28am UTC](https://discuss.elastic.co/t/detection-rules-triggered-although-ports-are-closed/266533/2 "2021-04-05T10:28:58Z")

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