GROK FILTER NOT WORKING WITH MULTILINE UNSTRUCTURED MESSAGE

Elastic Stack Logstash
1

Hello,

I am new to ELK stack and currently I am having issues with GROK filter.
My grok filter is working fine with the grok debugger http://grokdebug.herokuapp.com/. But when I try to use it on logstash then it is not able to display multiline logmessage on kibana .

My log example:
2019-03-06 07:35:00.4694|ERROR|Queue|Exception while processing Message 'f5cc33f4-9299-491a-8540-9fdaeb64d37a'
DETAILS: System.NullReferenceException: Object reference not set to an instance of an object.
at PublishingLogger.LogException(Exception Exception, Int32 id)
at Export.Export.Export(Message pm)
at Worker.PublishTrafficWorker.ProcessItems()
The server didn't respond in time.

here is my GROK filter:
match => ["message","(?(([0-9]+)-)+ ([0-9]+:)+.)|%{WORD:LOGLEVEL}|%{WORD:LOGSOURCE}|(?(.|\r|\n))" ]

Also try with below filter:
(?(([0-9]+)-)+ ([0-9]+:)+.*)|%{WORD:LOGLEVEL}|%{WORD:LOGSOURCE}|%{GREEDYDATA:LOGMESSAGE}

Bot both are display only first line.

Any suggestions/help is highly appreciated.

2

Have you taken a look at multiline yet?
https://www.elastic.co/guide/en/logstash/current/plugins-codecs-multiline.html

You may have to enable this on whatever beats that you are using rather than logstash.

3

Thanks for your reply Ken.

Instead of multiline codec I am using multiline.pattern: '^(?m)' in the filebeat.yml file.

but nothing happened.

Can you please help me the above mentioned log example.

4

What do you have in your mutliline setting in your filebeat.yml?

This is what my multi line looks like in my filebeat.yml

multiline.pattern: '^[[:space:]]'
multiline.negate: false
multiline.match: after

I use this for processing stacktraces after an error in one of my log files.

5

I am using
multiline.pattern: '^['
multiline.negate: true
multiline.match: after

6

Are you receiving all of the multilines on a single line on your logstash server?
Meaning that if you don't grok anything, are you receiving the correct multiline data on the logstash server?

Can you share what that one line the logstash server reports is?

7

No . I am getting only first line of message in LOGMESSAGE field
Below is the single line message which is diaplay on kibana:
Exception while processing Message 'f5cc33f4-9299-491a-8540-9fdaeb64d37a'

Without grok pattren I am getting whole message.

8

Okay, this means that your multiline section isn't working.
When multiline processes, it will combine all of the lines together onto a single line that it sends to logstash.
From there you will grok that single line message into how you want to break it out.

I am in the middle of something right now, but if I get a chance, I will try and test out what you have and see if I can fix the multiline in filebeat for you.

9

Thanks In advance Ken.

I am waiting for your response.
Meanwhile I am trying to find out the solution.searching on google to find out something which is helpfull for me.

10

Alright, I just went through and created something quick and dirty to get this working.
In your filebeat.yml you should have something that looks similar to this:

filebeat.inputs:

# Each - is an input. Most options can be set at the input level, so
# you can use different inputs for various configurations.
# Below are the input specific configurations.

- type: log

  # Change to true to enable this input configuration.
  enabled: true

  # Paths that should be crawled and fetched. Glob based paths.
  paths:
    - /root/ForumHelp.log
  fields:
    forum: true
  multiline.pattern: '^[0-9]{4}-[0-9]{2}-[0-9]{2}'
  multiline.negate: true
  multiline.match: after

This will send a single line to logstash. From there you can go through and build a grok to parse out the data into whatever fields that you wish.

11

Hi Ken,

I am using the same configuration in the filebeat.yml file
with grok filter in logstash
filter {

grok {
match => ["message","(?(([0-9]+)-)+ ([0-9]+:)+.*)|%{WORD:LOGLEVEL}|%{WORD:LOGSOURCE}|%{GREEDYDATA:LOGMESSAGE}"]
}
}

but still this is not working at my end on kibana

12

Remove your grok filter altogether. Verify that you are receiving all of your data in one "message" on logstash.

Post your results here once you have accomplished that.

If something is broken, or not working the way you want, you should break things down. Testing one thing at a time until you find what is actually causing the problem, then fixing that one thing.

When I attempted to test your logs, I found that I wasn't receiving a single line, as I had mismatched tabs in my filebeat.yml. Once I fixed that, then I was able to get everything on a single line.

13

Thanks for the reply Ken.

May be I am wrong to explain.

Now I have removed grok filter & verified with the get api
GET testlog-2019.03.15/_search
I am not receiving all data in one message
it break the data in multiple message.

14

That means that you have an error in your filebeat.yml that you need to fix. My assumption is that it was the same problem that I had where you don't have your multiline.X tabbed in correctly.

Can you post your entire filebeat.yml?

Once we get everything on one line, then we can start to play with the grok to get it to where it breaks out the data the way that you want.

15

format was quite odd while pasting it here.

16

Put it in
[ code]
[ /code]

Remove the space before code and before /code.

17

removed dirty data

18

Remove the spaces after the [
So it looks like this:
2019-03-15%2010_14_29-Window

19 

#=========================== Filebeat inputs =============================

 
filebeat.inputs:

filebeat.prospectors:

- type: log

  # Change to true to enable this input configuration.
  enabled: true

  # Paths that should be crawled and fetched. Glob based paths.
  paths:
    # - /var/log/*.log
     - c:\logfile\*
    #- c:\programdata\elasticsearch\logs\*

  # Exclude lines. A list of regular expressions to match. It drops the lines that are
  # matching any regular expression from the list.
  #exclude_lines: ['^DBG']

  # Include lines. A list of regular expressions to match. It exports the lines that are
  # matching any regular expression from the list.
  #include_lines: ['^ERR', '^WARN']

  # Exclude files. A list of regular expressions to match. Filebeat drops the files that
  # are matching any regular expression from the list. By default, no files are dropped.
  #exclude_files: ['.gz$']

  # Optional additional fields. These fields can be freely picked
  # to add additional information to the crawled log files for filtering
  fields:
   level: debug
   review: 1
   forum: true

  ### Multiline options

  # Multiline can be used for log messages spanning multiple lines. This is common
  # for Java Stack Traces or C-Line Continuation

  # The regexp Pattern that has to be matched. The example pattern matches all lines starting with [
   multiline.pattern: '^[0-9]{4}-[0-9]{2}-[0-9]{2}'

  # Defines if the pattern set under pattern should be negated or not. Default is false.
   multiline.negate: true

  # Match can be set to "after" or "before". It is used to define if lines should be append to a pattern
  # that was (not) matched before or after or as long as a pattern is not matched based on negate.
  # Note: After is the equivalent to previous and before is the equivalent to to next in Logstash
   multiline.match: after


#============================= Filebeat modules ===============================

filebeat.config.modules:
  # Glob pattern for configuration loading
  path: ${path.config}/modules.d/*.yml

  # Set to true to enable config reloading
  reload.enabled: true

  # Period on which files under path should be checked for changes
  #reload.period: 10s

#==================== Elasticsearch template setting ==========================

setup.template.settings:
  index.number_of_shards: 3
  #index.codec: best_compression
  #_source.enabled: false

#================================ General =====================================

# The name of the shipper that publishes the network data. It can be used to group
# all the transactions sent by a single shipper in the web interface.
#name:

# The tags of the shipper are included in their own field with each
# transaction published.
#tags: ["service-X", "web-tier"]

# Optional fields that you can specify to add additional information to the
# output.
fields:
  env: staging


#============================== Dashboards =====================================
# These settings control loading the sample dashboards to the Kibana index. Loading
# the dashboards is disabled by default and can be enabled either by setting the
# options here, or by using the `-setup` CLI flag or the `setup` command.
#setup.dashboards.enabled: false

# The URL from where to download the dashboards archive. By default this URL
# has a value which is computed based on the Beat name and version. For released
# versions, this URL points to the dashboard archive on the artifacts.elastic.co
# website.
#setup.dashboards.url:

#============================== Kibana =====================================

# Starting with Beats version 6.0.0, the dashboards are loaded via the Kibana API.
# This requires a Kibana endpoint configuration.
setup.kibana:

  # Kibana Host
  # Scheme and port can be left out and will be set to the default (http and 5601)
  # In case you specify and additional path, the scheme is required: http://localhost:5601/path
  # IPv6 addresses should always be defined as: https://[2001:db8::1]:5601
  host: "localhost:5601"

  # Kibana Space ID
  # ID of the Kibana Space into which the dashboards should be loaded. By default,
  # the Default Space will be used.
  #space.id:

#============================= Elastic Cloud ==================================

# These settings simplify using filebeat with the Elastic Cloud (https://cloud.elastic.co/).

# The cloud.id setting overwrites the `output.elasticsearch.hosts` and
# `setup.kibana.host` options.
# You can find the `cloud.id` in the Elastic Cloud web UI.
#cloud.id:

# The cloud.auth setting overwrites the `output.elasticsearch.username` and
# `output.elasticsearch.password` settings. The format is `<user>:<pass>`.
#cloud.auth:

#================================ Outputs =====================================

# Configure what output to use when sending the data collected by the beat.

#-------------------------- Elasticsearch output ------------------------------
# output.elasticsearch:
  # Array of hosts to connect to.
  # hosts: ["localhost:9200"]

  # Enabled ilm (beta) to use index lifecycle management instead daily indices.
  # ilm.enabled: true

  # Optional protocol and basic auth credentials.
  #protocol: "https"
  #username: "elastic"
  #password: "changeme"

#----------------------------- Logstash output --------------------------------
output.logstash:
  # The Logstash hosts
  hosts: ["localhost:5044"]

  # Optional SSL. By default is off.
  # List of root certificates for HTTPS server verifications
  #ssl.certificate_authorities: ["/etc/pki/root/ca.pem"]

  # Certificate for SSL client authentication
  #ssl.certificate: "/etc/pki/client/cert.pem"

  # Client Certificate Key
  #ssl.key: "/etc/pki/client/cert.key"

#================================ Processors =====================================

# Configure processors to enhance or manipulate events generated by the beat.

processors:
  - add_host_metadata: ~
  - add_cloud_metadata: ~

#================================ Logging =====================================

# Sets log level. The default log level is info.
# Available log levels are: error, warning, info, debug
# logging.level: debug

# At debug level, you can selectively enable logging only for some components.
# To enable all selectors use ["*"]. Examples of other selectors are "beat",
# "publish", "service".
#logging.selectors: ["*"]
20

This is the complete filebeat.yml file.