Deriving insights from logs
Get to the root cause of an issue by using out-of-the-box options such as queries, time range, and fields. Search and analyze logs on the Explorer > Discover tab. The following figure highlights the options of the Discover page that help you in getting to the root cause of an issue:
You observed multiple log entries with 501 status in your Single Sign On application logs. It means that the service is unavailable and you want to keep it available all the time. Use the search options and narrow down the results to find the root cause. For quick references, add the filtered logs to dashboards.
The following video (2:53) illustrates how to analyze and visualize logs:
Index pattern overview
By default, an index pattern is created for you. All the logs are collected under this index pattern. You can neither delete this index pattern nor create a new one.
After archiving is enabled, a new index pattern is added to the Discover page in the format logarc_*. All the logs collected since the time archiving is enabled for your tenant are shown in the new index pattern. The data before archiving is enabled continues to show in the earlier index pattern. Archived and restored data are available in the new index pattern only. Therefore, to analyze logs collected after archiving is enabled, use the logarc_* index pattern.
Options to search for a specific information
Use the following options to search for a specific alphanumeric string:
- Search field: Enter the string that you are looking for in a field. The format is:
field_name:"search string". For example, to search for all logs where status 501 is reported, enter status:501.
- Filter: Click Add Filter and select a field. Operators are available as per the data type of the selected field. Enter the string and save the filter. For example, loglevel.keyword is error.
Options to filter search results by time range and date
You get the following options to set the date to narrow down your search results:
- Specify days or hours for which you want to search results. For example, search results for last 15 minutes or last 7 days.
- Set specific date and time (absolute or specific). For example, search results for Jul 18, 2022 18:00 hours till Jul 19, 2022 18:00 hours.
Supported time formats
The log generation time is saved in the @timestamp field. Time of the collected logs must be in the ISO 8601 ZULU format; for example, 2022-02-20T12:21:32.756Z. If the log generation time is specified in any other format, it is saved in the @@timestamp field, and the log collection time is saved in the @timestamp field. The log collection time is available in the Greenwich Mean Time (GMT) time zone.
If you are collecting logs by using an external agent like Logstash and Filebeat, the Epoch time format is supported. However, if you are collecting logs by using the Docker, Windows, or Linux connector, the Epoch time format is not supported.
Fields available to filter logs
The fields identified in the logs are displayed in the Available fields section. Click a field and select a value to filter logs based on the field. For example, click the ipAddress field and select an IP address to search for all logs where ipAddress is the selected value. To add a field as a column in the search result, click the + symbol that is shown when you move your mouse over the field name.
In place of the data type icon of a field, if you see the '?' sign, refresh the index on the index pattern page (Stack Management > Index pattern > index pattern name). Or, wait for around 5 minutes when the index is refreshed automatically and then refresh your browser.
After using these options that help you analyze logs, you see the filtered records that require immediate attention:
To save the search
Save the search query that you have created by using the search field, available fields, and time period fields. In future, access the saved search to get similar results.
- Click Save.
- Enter a name.
- To access the saved search, click Open.
To add the saved search to a visualization
- Select Visualize > Create new visualization.
- Select the type of visualization that you want to use.
For example, a line chart.
- Select the search that you have saved.
- Apply additional filters to the data and save the visualization.
- To add the visualization to a dashboard:
- Click Dashboard.
- Create a new dashboard or edit an existing one.
- Click Add and select the visualization.