# Debugging questions + advice request

**URL:** <https://discuss.elastic.co/t/debugging-questions-advice-request/120340>\
**Category:** Logstash\
**Created:** [February 18, 2018, 9:50am UTC](https://discuss.elastic.co/t/debugging-questions-advice-request/120340 "2018-02-18T09:50:56Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![aclowkey](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/aclowkey/32/51020_2.png) [@aclowkey](https://discuss.elastic.co/u/aclowkey)\
**Post date:** [February 18, 2018, 9:50am UTC](https://discuss.elastic.co/t/debugging-questions-advice-request/120340/1 "2018-02-18T09:50:56Z")

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Hi,

I've started using Logstash coming from different pipeline products and I find it hard to understand what's wrong with my pipelines when it doesn't behave as expected.

For example, I've copied one simple JDBC input to Elastc Output and i get no documents. This is fine. Probably something is mis-configured or other issue.

The problem is, I don't get any logs, even when debug, it's at minimum and I have no indication if the username is wrong, or the query syntax is wrong, or even if the input tried to be executed.

I also don't know how to see how one event looks at a particular logstash, is there a LogEvent filter which can log it somehow?

Any advice from experienced logstash user on how you debug your pipelines from start to finish? Thanks

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**Author:** ![magnusbaeck](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/magnusbaeck/32/44943_2.png) [@magnusbaeck](https://discuss.elastic.co/u/magnusbaeck)\
**Post date:** [February 19, 2018, 10:03am UTC](https://discuss.elastic.co/t/debugging-questions-advice-request/120340/2 "2018-02-19T10:03:47Z")

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> The problem is, I don't get any logs, even when debug, it's at minimum and I have no indication if the username is wrong, or the query syntax is wrong, or even if the input tried to be executed.

With debug logging enabled you should get _something_, but if the problem is very early there might not be much to log.

> I also don't know how to see how one event looks at a particular logstash, is there a LogEvent filter which can log it somehow?

I don't understand what a "LogEvent filter" would do, but you can e.g. use a file our a stdout output to dump the events to something other than Elasticsearch.

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<div class="post-metadata">

**Author:** ![aclowkey](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/aclowkey/32/51020_2.png) [@aclowkey](https://discuss.elastic.co/u/aclowkey)\
**Post date:** [February 19, 2018, 10:27am UTC](https://discuss.elastic.co/t/debugging-questions-advice-request/120340/3 "2018-02-19T10:27:41Z")

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Say I have a complex pipeline with 20 ~ filters and something is not as expected at one point while filtering. I would like to know what my event looks live before I'm trying to split it, etc.

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**Author:** ![magnusbaeck](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/magnusbaeck/32/44943_2.png) [@magnusbaeck](https://discuss.elastic.co/u/magnusbaeck)\
**Post date:** [February 19, 2018, 10:37am UTC](https://discuss.elastic.co/t/debugging-questions-advice-request/120340/4 "2018-02-19T10:37:41Z")

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Okay. I haven't heard of someone making such a filter but it should be trivial. In the meantime you could use a ruby filter with a line or two of custom ruby code for dumping the event.

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**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\
**Post date:** [March 19, 2018, 10:37am UTC](https://discuss.elastic.co/t/debugging-questions-advice-request/120340/5 "2018-03-19T10:37:43Z")

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