If fluent-plugin-opensearch faied to refresh @_aws_credentials, it won't refresh @_aws_credentials anymore

[aYukiSekiguchi]

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Steps to replicate

There is no reliable steps to replicate.

When it failed to refresh @_aws_credentials like the following error log:

2024-02-23 22:16:07 +0000 [error]: #0 Unexpected error raised. Stopping the timer. title=:out_opensearch_expire_credentials error_class=RuntimeError error="No valid AWS credentials found."
  2024-02-23 22:16:07 +0000 [error]: #0 /opt/fluent/lib/ruby/gems/3.2.0/gems/fluent-plugin-opensearch-1.1.4/lib/fluent/plugin/out_opensearch.rb:252:in `aws_credentials'
  2024-02-23 22:16:07 +0000 [error]: #0 /opt/fluent/lib/ruby/gems/3.2.0/gems/fluent-plugin-opensearch-1.1.4/lib/fluent/plugin/out_opensearch.rb:353:in `block (2 levels) in configure'
  2024-02-23 22:16:07 +0000 [error]: #0 /opt/fluent/lib/ruby/gems/3.2.0/gems/fluent-plugin-opensearch-1.1.4/lib/fluent/plugin/out_opensearch.rb:351:in `synchronize'
  2024-02-23 22:16:07 +0000 [error]: #0 /opt/fluent/lib/ruby/gems/3.2.0/gems/fluent-plugin-opensearch-1.1.4/lib/fluent/plugin/out_opensearch.rb:351:in `block in configure'
  2024-02-23 22:16:07 +0000 [error]: #0 /opt/fluent/lib/ruby/gems/3.2.0/gems/fluentd-1.16.3/lib/fluent/plugin_helper/timer.rb:80:in `on_timer'
  2024-02-23 22:16:07 +0000 [error]: #0 /opt/fluent/lib/ruby/gems/3.2.0/gems/cool.io-1.8.0/lib/cool.io/loop.rb:88:in `run_once'
  2024-02-23 22:16:07 +0000 [error]: #0 /opt/fluent/lib/ruby/gems/3.2.0/gems/cool.io-1.8.0/lib/cool.io/loop.rb:88:in `run'
  2024-02-23 22:16:07 +0000 [error]: #0 /opt/fluent/lib/ruby/gems/3.2.0/gems/fluentd-1.16.3/lib/fluent/plugin_helper/event_loop.rb:93:in `block in start'
  2024-02-23 22:16:07 +0000 [error]: #0 /opt/fluent/lib/ruby/gems/3.2.0/gems/fluentd-1.16.3/lib/fluent/plugin_helper/thread.rb:78:in `block in thread_create'

It stopped to refresh with dumping the following log:

2024-02-23 22:16:07 +0000 [error]: #0 Timer detached. title=:out_opensearch_expire_credentials

Therefore, it will fail to flush the buffer with The security token included in the request is expired error message in the future.

FYI: The following is my config, but I don't think this depends on config.

<match apiserver>
  @type copy
  <store>
    @type s3
    <!-- skip -->
  </store>
  <store>
    @type opensearch
    bulk_message_request_threshold 6m
    request_timeout 90s
    resurrect_after 5s
    reload_connections false
    logstash_format true
    logstash_prefix apiserver
    logstash_dateformat %Y.%m.%d
    suppress_type_name true
    time_key time
    include_tag_key true
    tag_key @tag
    id_key _hash
    remove_keys _hash
    <buffer>
      @type file
      path /var/log/fluent/buffer/os/apiserver
      chunk_limit_size 60m
      flush_mode interval
      flush_interval 10s
      flush_at_shutdown true
    </buffer>
    <endpoint>
      url <URL to AWS OpenSearch Service>
      region ap-northeast-1
    </endpoint>
  </store>
</match>

Expected Behavior or What you need to ask

I'm not sure whether this is bug, but I want fluent-plugin-opensearch to refresh @_aws_credentials at the next refresh_credentials_interval. I guess AssumeRoleCredentials.new() failes if a network is unstable. If this happens, fluent-plugin-opensearch stops sending logs. I'm not happy with this.

The reason why fluent-plugin-opensearch stops to refresh @_aws_credentials is that timer_execute() removes the timer if its block raises an exeption.
https://github.com/fluent/fluentd/blob/2b4ca5d2927b706c3bdc98ffd0a0b66232bc0b65/lib/fluent/plugin_helper/timer.rb#L84-L85

Using Fluentd and OpenSearch plugin versions

• OS version: Amazon Linux 2
• Bare Metal or within Docker or Kubernetes or others?: Bare Metal
• Fluentd v1.0 or later: fluentd 1.16.3
• OpenSearch plugin version: fluent-plugin-opensearch (1.1.4)
• OpenSearch version (optional): 1.3
• OpenSearch template(s) (optional)

[aYukiSekiguchi]

We are running 6 instances with this plugin for about 1 month. We faced this bug in 3 out of 6 instances. Therefore, this isn't rare problem.

[davidpsv17]

It is happening the same to me with the same plugin version

[akhil31415]

@ashie san, Could you please confirm if there's any update for this issue?