SSL error - state=SSLv2/v3 read server hello A: unknown protocol (OpenSSL::SSL::SSLError)

[ruby4mag]

Hello,

I am getting ssl error while using the following config - rails

config/application.rb

require_relative 'boot'
  require 'rails/all'
  Bundler.require(*Rails.groups)
 module Myapp
    class Application < Rails::Application
    config.load_defaults 5.1
    OpenTelemetry::SDK.configure do |c|
       c.service_name = 'jaeger-example'
       c.use_all
    end
   tracer = OpenTelemetry.tracer_provider.tracer('rails')
  end

otlp-exporter.yaml

receivers:
   otlp:
      protocols:
          http:
          grpc:
exporters:
    logging:
      loglevel: debug
    tanzuobservability:
      traces:
        endpoint: "http://tracer.example.com:30000"
processors:
    batch:
      timeout: 20s

service:
    pipelines:
      traces:
        receivers: [otlp]
        exporters: [logging,tanzuobservability]
        processors: [batch]

And I am getting the following error when i access the application

Puma starting in single mode...
* Version 3.12.6 (ruby 2.6.3-p62), codename: Llamas in Pajamas
* Min threads: 5, max threads: 5
* Environment: production
* Listening on tcp://0.0.0.0:3000
Use Ctrl-C to stop
#<Thread:0x0000000004ead720@/usr/local/rvm/gems/ruby-2.6.3/gems/opentelemetry-sdk-0.17.0/lib/opentelemetry/sdk/trace/export/batch_span_processor.rb:180 run> terminated with exception (report_on_exception is true):
Traceback (most recent call last):
	21: from /usr/local/rvm/gems/ruby-2.6.3/gems/opentelemetry-sdk-0.17.0/lib/opentelemetry/sdk/trace/export/batch_span_processor.rb:180:in `block in reset_on_fork'
	20: from /usr/local/rvm/gems/ruby-2.6.3/gems/opentelemetry-sdk-0.17.0/lib/opentelemetry/sdk/trace/export/batch_span_processor.rb:159:in `work'
	19: from /usr/local/rvm/gems/ruby-2.6.3/gems/opentelemetry-sdk-0.17.0/lib/opentelemetry/sdk/trace/export/batch_span_processor.rb:159:in `loop'
	18: from /usr/local/rvm/gems/ruby-2.6.3/gems/opentelemetry-sdk-0.17.0/lib/opentelemetry/sdk/trace/export/batch_span_processor.rb:170:in `block in work'
	17: from /usr/local/rvm/gems/ruby-2.6.3/gems/opentelemetry-sdk-0.17.0/lib/opentelemetry/sdk/trace/export/batch_span_processor.rb:187:in `export_batch'
	16: from /usr/local/rvm/gems/ruby-2.6.3/gems/opentelemetry-sdk-0.17.0/lib/opentelemetry/sdk/trace/export/batch_span_processor.rb:187:in `synchronize'
	15: from /usr/local/rvm/gems/ruby-2.6.3/gems/opentelemetry-sdk-0.17.0/lib/opentelemetry/sdk/trace/export/batch_span_processor.rb:187:in `block in export_batch'
	14: from /usr/local/rvm/gems/ruby-2.6.3/gems/opentelemetry-exporter-otlp-0.17.0/lib/opentelemetry/exporter/otlp/exporter.rb:76:in `export'
	13: from /usr/local/rvm/gems/ruby-2.6.3/gems/opentelemetry-exporter-otlp-0.17.0/lib/opentelemetry/exporter/otlp/exporter.rb:143:in `send_bytes'
	12: from /usr/local/rvm/gems/ruby-2.6.3/gems/opentelemetry-exporter-otlp-0.17.0/lib/opentelemetry/exporter/otlp/exporter.rb:136:in `around_request'
	11: from /usr/local/rvm/gems/ruby-2.6.3/gems/opentelemetry-common-0.17.0/lib/opentelemetry/common/utilities.rb:60:in `untraced'
	10: from /usr/local/rvm/gems/ruby-2.6.3/gems/opentelemetry-api-0.17.0/lib/opentelemetry/trace.rb:82:in `with_span'
	 9: from /usr/local/rvm/gems/ruby-2.6.3/gems/opentelemetry-api-0.17.0/lib/opentelemetry/context.rb:62:in `with_value'
	 8: from /usr/local/rvm/gems/ruby-2.6.3/gems/opentelemetry-api-0.17.0/lib/opentelemetry/trace.rb:82:in `block in with_span'
	 7: from /usr/local/rvm/gems/ruby-2.6.3/gems/opentelemetry-common-0.17.0/lib/opentelemetry/common/utilities.rb:60:in `block in untraced'
	 6: from /usr/local/rvm/gems/ruby-2.6.3/gems/opentelemetry-exporter-otlp-0.17.0/lib/opentelemetry/exporter/otlp/exporter.rb:136:in `block in around_request'
	 5: from /usr/local/rvm/gems/ruby-2.6.3/gems/opentelemetry-exporter-otlp-0.17.0/lib/opentelemetry/exporter/otlp/exporter.rb:160:in `block in send_bytes'
	 4: from /usr/local/rvm/rubies/ruby-2.6.3/lib/ruby/2.6.0/net/http.rb:925:in `start'
	 3: from /usr/local/rvm/rubies/ruby-2.6.3/lib/ruby/2.6.0/net/http.rb:930:in `do_start'
	 2: from /usr/local/rvm/rubies/ruby-2.6.3/lib/ruby/2.6.0/net/http.rb:996:in `connect'
	 1: from /usr/local/rvm/rubies/ruby-2.6.3/lib/ruby/2.6.0/net/protocol.rb:44:in `ssl_socket_connect'
/usr/local/rvm/rubies/ruby-2.6.3/lib/ruby/2.6.0/net/protocol.rb:44:in `connect_nonblock': SSL_connect returned=1 errno=0 state=SSLv2/v3 read server hello A: unknown protocol (OpenSSL::SSL::SSLError)

Anyone faced this error or give any pointers to the fix?

# ruby -v
ruby 2.6.3p62 (2019-04-16 revision 67580) [x86_64-linux]
# ruby -ropenssl -e 'puts OpenSSL::OPENSSL_VERSION'
OpenSSL 1.0.2k  26 Jan 2017

[arielvalentin]

This error looks to me like you're trying to use the default secure connections (https) from the Rails app to send traces to the OTEL exporter.

If you're running this in an environment where you're not managing SSL certificates e.g. development, you'll need to use insecure connections (http).

Take a look at the docs for an example of how to do that:

https://opentelemetry.io/docs/ruby/getting_started/#exporting-traces

[ruby4mag]

Thanks @arielvalentin . It worked !