Elasticsearch troubleshooting

Use the following information to troubleshoot Elasticsearch issues.

View logs

One of the most valuable tools for identifying issues with the Elasticsearch integration are logs. The most relevant logs for this integration are:

  1. sidekiq.log - All of the indexing happens in Sidekiq, so much of the relevant logs for the Elasticsearch integration can be found in this file.
  2. elasticsearch.log - There are additional logs specific to Elasticsearch that are sent to this file that may contain useful diagnostic information about searching, indexing or migrations.

Here are some common pitfalls and how to overcome them.

How can I verify that my GitLab instance is using Elasticsearch?

There are a couple of ways to achieve that:

  • Whenever you perform a search there is a link on the search results page in the top right hand corner saying “Advanced search functionality is enabled”. This is always correctly identifying whether the current project/namespace being searched is using Elasticsearch.

  • From the Admin Area under Settings > Advanced Search check that the Advanced Search settings are checked.

    Those same settings there can be obtained from the Rails console if necessary:

    ::Gitlab::CurrentSettings.elasticsearch_search?         # Whether or not searches will use Elasticsearch
    ::Gitlab::CurrentSettings.elasticsearch_indexing?       # Whether or not content will be indexed in Elasticsearch
    ::Gitlab::CurrentSettings.elasticsearch_limit_indexing? # Whether or not Elasticsearch is limited only to certain projects/namespaces
    
  • If Elasticsearch is limited to specific namespaces and you need to know if Elasticsearch is being used for a specific project or namespace, you can use the Rails console:

    ::Gitlab::CurrentSettings.search_using_elasticsearch?(scope: Namespace.find_by_full_path("/my-namespace"))
    ::Gitlab::CurrentSettings.search_using_elasticsearch?(scope: Project.find_by_full_path("/my-namespace/my-project"))
    

I updated GitLab and now I can’t find anything

We continuously make updates to our indexing strategies and aim to support newer versions of Elasticsearch. When indexing changes are made, it may be necessary for you to reindex after updating GitLab.

I indexed all the repositories but I can’t get any hits for my search term in the UI

Make sure you indexed all the database data.

If there aren’t any results (hits) in the UI search, check if you are seeing the same results via the rails console (sudo gitlab-rails console):

u = User.find_by_username('your-username')
s = SearchService.new(u, {:search => 'search_term', :scope => 'blobs'})
pp s.search_objects.to_a

Beyond that, check via the Elasticsearch Search API to see if the data shows up on the Elasticsearch side:

curl --request GET <elasticsearch_server_ip>:9200/gitlab-production/_search?q=<search_term>

More complex Elasticsearch API calls are also possible.

It is important to understand at which level the problem is manifesting (UI, Rails code, Elasticsearch side) to be able to troubleshoot further.

note
The above instructions are not to be used for scenarios that only index a subset of namespaces.

See Elasticsearch Index Scopes for more information on searching for specific types of data.

I indexed all the repositories but then switched Elasticsearch servers and now I can’t find anything

You must re-run all the Rake tasks to reindex the database, repositories, and wikis.

The indexing process is taking a very long time

The more data present in your GitLab instance, the longer the indexing process takes.

There are some projects that weren’t indexed, but I don’t know which ones

You can run sudo gitlab-rake gitlab:elastic:projects_not_indexed to display projects that aren’t indexed.

No new data is added to the Elasticsearch index when I push code

note
This was fixed in GitLab 13.2 and the Rake task is not available for versions greater than that.

When performing the initial indexing of blobs, we lock all projects until the project finishes indexing. It could happen that an error during the process causes one or multiple projects to remain locked. To unlock them, run:

sudo gitlab-rake gitlab:elastic:clear_locked_projects

Can't specify parent if no parent field has been configured error

If you enabled Elasticsearch before GitLab 8.12 and have not rebuilt indices, you get exceptions in lots of different cases:

Elasticsearch::Transport::Transport::Errors::BadRequest([400] {
    "error": {
        "root_cause": [{
            "type": "illegal_argument_exception",
            "reason": "Can't specify parent if no parent field has been configured"
        }],
        "type": "illegal_argument_exception",
        "reason": "Can't specify parent if no parent field has been configured"
    },
    "status": 400
}):

This is because we changed the index mapping in GitLab 8.12 and the old indices should be removed and built from scratch again, see details in the update guide.

Elasticsearch::Transport::Transport::Errors::BadRequest

If you have this exception (just like in the case above but the actual message is different) please check if you have the correct Elasticsearch version and you met the other requirements. There is also an easy way to check it automatically with sudo gitlab-rake gitlab:check command.

Elasticsearch::Transport::Transport::Errors::RequestEntityTooLarge

[413] {"Message":"Request size exceeded 10485760 bytes"}

This exception is seen when your Elasticsearch cluster is configured to reject requests above a certain size (10MiB in this case). This corresponds to the http.max_content_length setting in elasticsearch.yml. Increase it to a larger size and restart your Elasticsearch cluster.

AWS has fixed limits for this setting (“Maximum size of HTTP request payloads”), based on the size of the underlying instance.

My single node Elasticsearch cluster status never goes from yellow to green even though everything seems to be running properly

For a single node Elasticsearch cluster the functional cluster health status is yellow (never green) because the primary shard is allocated but replicas cannot be as there is no other node to which Elasticsearch can assign a replica. This also applies if you are using the Amazon OpenSearch service.

caution
Setting the number of replicas to 0 is discouraged (this is not allowed in the GitLab Elasticsearch Integration menu). If you are planning to add more Elasticsearch nodes (for a total of more than 1 Elasticsearch) the number of replicas needs to be set to an integer value larger than 0. Failure to do so results in lack of redundancy (losing one node corrupts the index).

If you have a hard requirement to have a green status for your single node Elasticsearch cluster, please make sure you understand the risks outlined in the previous paragraph and then run the following query to set the number of replicas to 0(the cluster no longer tries to create any shard replicas):

curl --request PUT localhost:9200/gitlab-production/_settings --header 'Content-Type: application/json' \
     --data '{
       "index" : {
         "number_of_replicas" : 0
       }
     }'

health check timeout: no Elasticsearch node available error in Sidekiq

If you’re getting a health check timeout: no Elasticsearch node available error in Sidekiq during the indexing process:

Gitlab::Elastic::Indexer::Error: time="2020-01-23T09:13:00Z" level=fatal msg="health check timeout: no Elasticsearch node available"

You probably have not used either http:// or https:// as part of your value in the “URL” field of the Elasticsearch Integration Menu. Please make sure you are using either http:// or https:// in this field as the Elasticsearch client for Go that we are using needs the prefix for the URL to be accepted as valid. After you have corrected the formatting of the URL, delete the index (via the dedicated Rake task) and reindex the content of your instance.

My Elasticsearch cluster has a plugin and the integration is not working

Certain 3rd party plugins may introduce bugs in your cluster or for whatever reason may be incompatible with our integration. You should try disabling plugins so you can rule out the possibility that the plugin is causing the problem.

Low-level troubleshooting

There is a more structured, lower-level troubleshooting document for when you experience other issues, including poor performance.

Elasticsearch code_analyzer doesn’t account for all code cases

The code_analyzer pattern and filter configuration is being evaluated for improvement. We have fixed most edge cases that were not returning expected search results due to our pattern and filter configuration.

Improvements to the code_analyzer pattern and filters are being discussed in epic 3621.

Some binary files may not be searchable by name

In GitLab 13.9, a change was made where binary file names are being indexed. However, without indexing all projects’ data from scratch, only binary files that are added or updated after the GitLab 13.9 release are searchable.

Last resort to recreate an index

There may be cases where somehow data never got indexed and it’s not in the queue, or the index is somehow in a state where migrations just cannot proceed. It is always best to try to troubleshoot the root cause of the problem by viewing the logs.

If there are no other options, then you always have the option of recreating the entire index from scratch. If you have a small GitLab installation, this can sometimes be a quick way to resolve a problem, but if you have a large GitLab installation, then this might take a very long time to complete. Until the index is fully recreated, your index does not serve correct search results, so you may want to disable Search with Elasticsearch while it is running.

If you are sure you’ve read the above caveats and want to proceed, then you should run the following Rake task to recreate the entire index from scratch:

For Omnibus installations

# WARNING: DO NOT RUN THIS UNTIL YOU READ THE DESCRIPTION ABOVE
sudo gitlab-rake gitlab:elastic:index

For installations from source

# WARNING: DO NOT RUN THIS UNTIL YOU READ THE DESCRIPTION ABOVE
cd /home/git/gitlab
sudo -u git -H bundle exec rake gitlab:elastic:index

How does Advanced Search ha