Hi, after some time of using newly deployed kolla-ansible I have fluentd errors: on all controllers, storage and network nodes: /var/log/kolla/fluentd/fluentd.log:2021-09-27 01:40:46 +0200 [warn]: #0 failed to flush the buffer. retry_time=0 next_retry_seconds=2021-09-27 01:40:47.847564807 +0200 chunk="5ccee7b1762157f0ae10dcbeb4e14fd8" error_class=RestClient::GatewayTimeout error="504 Gateway Timeout" /var/log/kolla/fluentd/fluentd.log:2021-09-27 04:49:31 +0200 [warn]: #0 failed to flush the buffer. retry_time=0 next_retry_seconds=2021-09-27 04:49:32.728326628 +0200 chunk="5ccf11fdc0d6876abdef813211371285" error_class=RestClient::RequestTimeout error="408 Request Timeout” on compute nodes: /var/log/kolla/fluentd/fluentd.log:2021-09-27 06:41:38 +0200 [warn]: #0 emit transaction failed: error_class=Fluent::Plugin::Buffer::BufferOverflowError error="buffer space has too many data" location="/opt/td-agent/lib/ruby/gems/2.7.0/gems/fluentd-1.11.2/lib/fluent/plugin/buffer.rb:293:in `write'" tag="openstack_python" /var/log/kolla/fluentd/fluentd.log:2021-09-27 06:41:38 +0200 [warn]: #0 emit transaction failed: error_class=Fluent::Plugin::Buffer::BufferOverflowError error="buffer space has too many data" location="/opt/td-agent/lib/ruby/gems/2.7.0/gems/fluentd-1.11.2/lib/fluent/plugin/buffer.rb:293:in `write'" tag="kolla.var.log.kolla.monasca.agent-statsd.log" /var/log/kolla/fluentd/fluentd.log:2021-09-27 06:41:38 +0200 [warn]: #0 emit transaction failed: error_class=Fluent::Plugin::Buffer::BufferOverflowError error="buffer space has too many data" location="/opt/td-agent/lib/ruby/gems/2.7.0/gems/fluentd-1.11.2/lib/fluent/plugin/buffer.rb:293:in `write'" tag="fluent.warn" /var/log/kolla/fluentd/fluentd.log:2021-09-27 06:41:38 +0200 [error]: #0 failed to emit fluentd's log event tag="fluent.warn" event={"action"=>:throw_exception, "message"=>"failed to write data into buffer by buffer overflow action=:throw_exception"} error_class=Fluent::Plugin::Buffer::BufferOverflowError error="buffer space has too many data" /var/log/kolla/fluentd/fluentd.log:2021-09-27 06:41:38 +0200 [warn]: #0 emit transaction failed: error_class=Fluent::Plugin::Buffer::BufferOverflowError error="buffer space has too many data" location="/opt/td-agent/lib/ruby/gems/2.7.0/gems/fluentd-1.11.2/lib/fluent/plugin/buffer.rb:293:in `write'" tag="fluent.warn" /var/log/kolla/fluentd/fluentd.log:2021-09-27 06:41:38 +0200 [error]: #0 failed to emit fluentd's log event tag="fluent.warn" event={"error"=>"#<Fluent::Plugin::Buffer::BufferOverflowError: buffer space has too many data>", "location"=>"/opt/td-agent/lib/ruby/gems/2.7.0/gems/fluentd-1.11.2/lib/fluent/plugin/buffer.rb:293:in `write'", "tag"=>"openstack_python", "message"=>"emit transaction failed: error_class=Fluent::Plugin::Buffer::BufferOverflowError error=\"buffer space has too many data\" location=\"/opt/td-agent/lib/ruby/gems/2.7.0/gems/fluentd-1.11.2/lib/fluent/plugin/buffer.rb:293:in `write'\" tag=\"openstack_python\""} error_class=Fluent::Plugin::Buffer::BufferOverflowError error="buffer space has too many data" /var/log/kolla/fluentd/fluentd.log:2021-09-27 06:41:38 +0200 [warn]: #0 emit transaction failed: error_class=Fluent::Plugin::Buffer::BufferOverflowError error="buffer space has too many data" location="/opt/td-agent/lib/ruby/gems/2.7.0/gems/fluentd-1.11.2/lib/fluent/plugin/buffer.rb:293:in `write'" tag="fluent.warn" /var/log/kolla/fluentd/fluentd.log:2021-09-27 06:41:38 +0200 [error]: #0 failed to emit fluentd's log event tag="fluent.warn" event={"error"=>"#<Fluent::Plugin::Buffer::BufferOverflowError: buffer space has too many data>", "location"=>"/opt/td-agent/lib/ruby/gems/2.7.0/gems/fluentd-1.11.2/lib/fluent/plugin/buffer.rb:293:in `write'", "tag"=>"kolla.var.log.kolla.monasca.agent-statsd.log", "message"=>"emit transaction failed: error_class=Fluent::Plugin::Buffer::BufferOverflowError error=\"buffer space has too many data\" location=\"/opt/td-agent/lib/ruby/gems/2.7.0/gems/fluentd-1.11.2/lib/fluent/plugin/buffer.rb:293:in `write'\" tag=\"kolla.var.log.kolla.monasca.agent-statsd.log\""} error_class=Fluent::Plugin::Buffer::BufferOverflowError error="buffer space has too many data" /var/log/kolla/fluentd/fluentd.log:2021-09-27 06:41:38 +0200 [warn]: #0 emit transaction failed: error_class=Fluent::Plugin::Buffer::BufferOverflowError error="buffer space has too many data" location="/opt/td-agent/lib/ruby/gems/2.7.0/gems/fluentd-1.11.2/lib/fluent/plugin/buffer.rb:293:in `write'" tag="openstack_python" /var/log/kolla/fluentd/fluentd.log:2021-09-27 06:41:38 +0200 [warn]: #0 emit transaction failed: error_class=Fluent::Plugin::Buffer::BufferOverflowError error="buffer space has too many data" location="/opt/td-agent/lib/ruby/gems/2.7.0/gems/fluentd-1.11.2/lib/fluent/plugin/buffer.rb:293:in `write'" tag="fluent.warn" /var/log/kolla/fluentd/fluentd.log:2021-09-27 06:41:38 +0200 [warn]: #0 emit transaction failed: error_class=Fluent::Plugin::Buffer::BufferOverflowError error="buffer space has too many data" location="/opt/td-agent/lib/ruby/gems/2.7.0/gems/fluentd-1.11.2/lib/fluent/plugin/buffer.rb:293:in `write'" tag="kolla.var.log.kolla.monasca.agent-forwarder.log" /var/log/kolla/fluentd/fluentd.log:2021-09-27 06:41:38 +0200 [error]: #0 failed to emit fluentd's log event tag="fluent.warn" event={"action"=>:throw_exception, "message"=>"failed to write data into buffer by buffer overflow action=:throw_exception"} error_class=Fluent::Plugin::Buffer::BufferOverflowError error="buffer space has too many data” and on monitoring node: 2021-09-27 14:40:50 +0200 [warn]: #0 buffer flush took longer time than slow_flush_log_threshold: elapsed_time=84.05643947119825 slow_flush_log_threshold=20.0 plugin_id="object:bff4" 2021-09-27 14:42:53 +0200 [warn]: #0 buffer flush took longer time than slow_flush_log_threshold: elapsed_time=122.65328024700284 slow_flush_log_threshold=20.0 plugin_id="object:bff4" 2021-09-27 14:44:15 +0200 [warn]: #0 buffer flush took longer time than slow_flush_log_threshold: elapsed_time=82.32426812895574 slow_flush_log_threshold=20.0 plugin_id="object:bff4" 2021-09-27 14:46:05 +0200 [warn]: #0 Bulk sending messages to monasca-api threw exception exceptionew=#<RestClient::Exceptions::ReadTimeout: Timed out reading data from server> 2021-09-27 14:46:05 +0200 [warn]: #0 failed to flush the buffer. retry_time=0 next_retry_seconds=2021-09-27 14:46:06.042150289 +0200 chunk="5ccf89c9ec54b09e616f7167d5f93cc1" error_class=RestClient::Exceptions::ReadTimeout error="Timed out reading data from server" 2021-09-27 14:46:05 +0200 [warn]: #0 suppressed same stacktrace 2021-09-27 14:47:58 +0200 [warn]: #0 buffer flush took longer time than slow_flush_log_threshold: elapsed_time=112.90601075813174 slow_flush_log_threshold=20.0 plugin_id="object:bff4" 2021-09-27 14:47:58 +0200 [warn]: #0 retry succeeded. chunk_id="5ccf89c9ec54b09e616f7167d5f93cc1" 2021-09-27 14:50:16 +0200 [warn]: #0 buffer flush took longer time than slow_flush_log_threshold: elapsed_time=136.24769522389397 slow_flush_log_threshold=20.0 plugin_id="object:bff4" 2021-09-27 14:52:27 +0200 [warn]: #0 buffer flush took longer time than slow_flush_log_threshold: elapsed_time=129.86474119895138 slow_flush_log_threshold=20.0 plugin_id="object:bff4" 2021-09-27 14:54:08 +0200 [warn]: #0 buffer flush took longer time than slow_flush_log_threshold: elapsed_time=100.71324555086903 slow_flush_log_threshold=20.0 plugin_id="object:bff4" 2021-09-27 14:56:31 +0200 [warn]: #0 Bulk sending messages to monasca-api threw exception exceptionew=#<RestClient::Exceptions::ReadTimeout: Timed out reading data from server> 2021-09-27 14:56:31 +0200 [warn]: #0 failed to flush the buffer. retry_time=0 next_retry_seconds=2021-09-27 14:56:32.140741991 +0200 chunk="5ccf89e1feb471b7ce25a26d37977baa" error_class=RestClient::Exceptions::ReadTimeout error="Timed out reading data from server" 2021-09-27 14:56:31 +0200 [warn]: #0 suppressed same stacktrace 2021-09-27 14:58:03 +0200 [warn]: #0 buffer flush took longer time than slow_flush_log_threshold: elapsed_time=90.91785193886608 slow_flush_log_threshold=20.0 plugin_id="object:bff4" 2021-09-27 14:58:03 +0200 [warn]: #0 retry succeeded. chunk_id="5ccf89e1feb471b7ce25a26d37977baa" 2021-09-27 15:00:01 +0200 [info]: #0 detected rotation of /var/log/kolla/kafka/server.log; waiting 5 seconds 2021-09-27 15:00:01 +0200 [info]: #0 following tail of /var/log/kolla/kafka/server.log 2021-09-27 15:00:10 +0200 [warn]: #0 buffer flush took longer time than slow_flush_log_threshold: elapsed_time=127.54797655600123 slow_flush_log_threshold=20.0 plugin_id="object:bff4" 2021-09-27 15:02:29 +0200 [warn]: #0 buffer flush took longer time than slow_flush_log_threshold: elapsed_time=137.74220423400402 slow_flush_log_threshold=20.0 plugin_id="object:bff4" 2021-09-27 15:03:08 +0200 [warn]: #0 buffer flush took longer time than slow_flush_log_threshold: elapsed_time=38.81670297612436 slow_flush_log_threshold=20.0 plugin_id="object:bff4" 2021-09-27 15:03:13 +0200 [info]: #0 detected rotation of /var/log/kolla/kafka/controller.log; waiting 5 seconds 2021-09-27 15:03:13 +0200 [info]: #0 following tail of /var/log/kolla/kafka/controller.log What seems to be the problem? Is there any way to run more than one fluentd worker in kolla? Best regards Adam Tomas