This document provides information on what Kibana is, how to search it, interpret its results, and contains tips and tricks on getting specific information from it.
Kibana is an open source data visualization plugin for Elasticsearch. It provides visualization capabilities on top of the content indexed on an Elasticsearch cluster. Support Engineering uses Kibana to both search for error events on GitLab.com and to detect when specific changes were made to various aspects of it by a user.
Knowing where to search in Kibana is paramount to getting the proper results. The area of the application (GitLab.com) that you're searching is known as the Index in Kibana. The default index used for searching is pubsub-rails-inf-gprd-* but you can change this by clicking the (change) button:
For example, if you're trying to track down failed logins you would search the index pubsub-application-inf-gprd*. To search for 500 errors involving a controller you'd search in pubsub-rails-inf-gprd-*, the default index.
Along with the index, knowing when a specific error or event ocurred that you're trying to track down is important and it's important to keep in mind that Kibana logs on GitLab.com persist for seven days. Kibana allows you to choose relative and absolute time ranges for search results and this can be changed by manipulating the date range:
Each log entry is comprised of a number of Fields in which the specific information about the entry is displayed. Knowing which fields to apply to your search results and how to filter for them is just as important as knowing where and when to search. The most important fields are:
json.methodjson.actionjson.controller - for more on this see the controller definitions in the GitLab sourcecodejson.statusjson.pathAll available fields are displayed along the left-hand side menu and you can add them to your search results by hovering over each and clicking the add button.
If you don't filter for specific fields it can be difficult to find specific log entries if a large number of them are returned on your search query.
For example, we're trying to locate any log events generated by the GitLab.com user tristan that returned a 404 status code within the last 15 minutes. We can start by searching the pubsub-rails-inf-gprd-* index for json.username : tristan within that time range and we'd get results similar to the following once we click add next to the json.status field along the left-hand side bar:
The majority of results as entries that returned 200, which aren't in the scope of what we're looking for. To search for results where 404 was returned we can click + Add Filter underneath the search bar and place a positive filter on json.status is 404, which will give us these results, exactly what we're looking for.
This section details how you can find very specific pieces of information in Kibana by searching for and filtering out specific fields. Each tip includes a link to the group, subgroup, or project that was used in the example for reference.
Example group: gitlab-bronze
We can determine if the GitLab Runner registration token was reset for a group or project and see which user reset it and when. For this example the Runner registration token was reset at the group-level in gitlab-bronze. To find the log entry:
Last 7 days if you're unsure.json.path for the path of the group, which is just gitlab-bronze in this example.json.action for reset_registration_token.json.username field of the result.Kibana can be used to determine who triggered the deletion of a group, subgroup, or project on GitLab.com. To find the log entry:
Last 7 days if you're unsure.json.path for the path of the project, including the group and subgroup, if applicable. This is gitlab-silver/test-project-to-delete in this example.json.method for DELETE.json.username field of the result.