# Add Sub fields

**URL:** <https://discuss.elastic.co/t/add-sub-fields/243414>\
**Category:** Logstash\
**Created:** [August 1, 2020, 3:17am UTC](https://discuss.elastic.co/t/add-sub-fields/243414 "2020-08-01T03:17:47Z")\
**Posts on this page:** 6\
**Page:** 1

<div class="post-metadata">

**Author:** ![nurhambali](https://avatars.discourse-cdn.com/v4/letter/n/3ec8ea/32.png) [@nurhambali](https://discuss.elastic.co/u/nurhambali)\
**Post date:** [August 1, 2020, 3:17am UTC](https://discuss.elastic.co/t/add-sub-fields/243414/1 "2020-08-01T03:17:48Z")

</div>

hi,

how to add sub fields on logstash ex: server, time, message

i'm add sub field modsec.server modsec.time modsec.message ?

any ide ?

---

<div class="post-metadata">

**Author:** ![Jenni](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/jenni/32/29684_2.png) [@Jenni](https://discuss.elastic.co/u/Jenni)\
**Post date:** [August 1, 2020, 3:36am UTC](https://discuss.elastic.co/t/add-sub-fields/243414/2 "2020-08-01T03:36:26Z")

</div>

This link explains the Logstash field syntax: [https://www.elastic.co/guide/en/logstash/current/event-dependent-configuration.html#logstash-config-field-references](https://www.elastic.co/guide/en/logstash/current/event-dependent-configuration.html#logstash-config-field-references)

```auto
mutate {
  add_field => { "[modsec][server]" => "something" } 
} 

```

---

<div class="post-metadata">

**Author:** ![nurhambali](https://avatars.discourse-cdn.com/v4/letter/n/3ec8ea/32.png) [@nurhambali](https://discuss.elastic.co/u/nurhambali)\
**Post date:** [August 1, 2020, 3:43am UTC](https://discuss.elastic.co/t/add-sub-fields/243414/3 "2020-08-01T03:43:39Z")

</div>

whether to do it one by one fields ?  
what if i want all fields to add sub fields ?

---

<div class="post-metadata">

**Author:** ![Jenni](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/jenni/32/29684_2.png) [@Jenni](https://discuss.elastic.co/u/Jenni)\
**Post date:** [August 1, 2020, 4:27am UTC](https://discuss.elastic.co/t/add-sub-fields/243414/4 "2020-08-01T04:27:30Z")

</div>

I think I don't understand the question? Do you want to move every single field of your event from the root to modsec? If you have a few fields that already exist and that should be moved, you would use the rename option of the mutate filter. If there is a dynamic number of fields in your event that should all be moved, you could use Ruby to iterate over them.

---

<div class="post-metadata">

**Author:** ![nurhambali](https://avatars.discourse-cdn.com/v4/letter/n/3ec8ea/32.png) [@nurhambali](https://discuss.elastic.co/u/nurhambali)\
**Post date:** [August 1, 2020, 4:38am UTC](https://discuss.elastic.co/t/add-sub-fields/243414/5 "2020-08-01T04:38:30Z")

</div>

oke thanks i will move all field to root modsec, and i configure mutate one by one field.

thank you for the advice

---

<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:** [August 29, 2020, 4:38am UTC](https://discuss.elastic.co/t/add-sub-fields/243414/6 "2020-08-29T04:38:33Z")

</div>

This topic was automatically closed 28 days after the last reply. New replies are no longer allowed.