Just because 2.0 isn’t required to be backward compatible doesn’t mean we can ignore usability for current users. When we remove something people use we should replace it with a clear error so people know a change has been made and they need to adapt.

The errors should recommend a migration path or actively allow users push an update to their config. For example, the udp_listener will be removed. If someone tries to use it there should be an error saying to migrate to socket_listener. It shouldn’t be a warning that the user can ignore, but instead be a fatal error that requires the user to adapt their config before continuing to use telegraf.

Deprecated

Entire Plugins

• inputs.cassandra -> inputs.jolokia2 w/ example cassandra.conf
• inputs.http_listener -> inputs.influxdb_listener (already renamed - make sure it's completely removed)
• inputs.httpjson -> inputs.http
• inputs.jolokia -> inputs.jolokia2
• inputs.kafka_consumer_legacy -> inputs.kafka_consumer
  inputs.kafka_consumer_legacy is the only way to use kafka version <0.8. When remove legacy plugin, note that plugin only supports Kafka v0.8+
• inputs.leofs -> inputs.snmp
• inputs.logparser -> inputs.tail
• inputs.snmp_legacy -> inputs.snmp
• inputs.tcp_listener -> inputs.socket_listener
• inputs.udp_listener -> inputs.socket_listener
• outputs.reimann_legacy -> outputs.reimann

Partially resolved in: #9609

Refactor plugins

• Consider combining directory_monitor, file, tail plugins #11108
• inputs.file. Rename to inputs.value_file to avoid confusion

Input plugin settings

• Activemq server and port
• Aerospike enable_ssl
• Amqp_consumer url
• Consul datacentre
• Disk mountpoints
• Docker container_names
• Docker perdevice
• Docker total
• Filecount directory
• Http_listener_v2 path
• Http_response address
• Httpjson name
• Influxdb_listener max_line_size
• Mongodb ssl_enabled and cacerts
• MQTT Consumer metric_buffer
• MQTT Consumer servers format without scheme
• NATS Consumer metric_buffer
• Nsq name
• Nsq_consumer server
• Openldap ssl and ssl_ca
• PostgreSQL address default value "local" instead of "localhost" #4872
• Rabbitmq name
• Rabbitmq queues
• Smart path
• Sqlserver query_version and azuredb
• Statsd convert_names
• Statsd parse_data_dog_tags
• Statsd udp_packet_size
• Vsphere force_discover_on_init
• Win_perfcounters PreVistaSupport
• Zookeeper enable_ssl

Output plugin settings

Resolved in: #11748

• AMQP database and retention_policy
• AMQP precision
• AMQP url
• Influxdb precision
• Influxdb url
• Kinesis partitionkey and use_random_partitionkey
• Librato source_tag
• Wavefront string_to_number subtable

Processor plugin settings

• ifName agent default value #8011

Serializers

• Should consider consistent behavior via Define an error handling behavior of Serializer.SerializeBatch function #8830

Common settings

• flush_buffer_when_full
• utc
• Kafka enable_tls
• TLS ssl_ca, ssl_cert and ssl_key

Metric formats

• System input plugin uptime_format field
• Prometheus input and prometheus_client output metric_version = 1 (May be more difficult than we think to remove)
• Consul input metric_version=1
• Minecraft input tag server
• Net_response input fields result_type and string_found
• Kube_inventory input field terminated_reason
• MySQL metric_version = 1 (only existed for backwards compatibility for those on < Telegraf 1.6)
• Standardize on tag representing the source host of the metrics #4413
• Procstat empty cpu fields [procstat] why keep these meaningless fields #11768

Internal APIs

• Metric interface: Tags(), Fields(), AddPrefix(), AddSuffix()
• plugins/inputs/execd/shim -> plugins/common/shim
• aggregators should not re-run processors #7993
• processors should run in the order they appear in the config #8016

Builds, Packaging

• feat: always disable cgo support (static builds) #10426

Support only one v1/v2 plugins

Remove version nomenclature from plugin

• JSON Parser
  • parsers.json
  • parsers.json_v2
• HTTP Listener Input
  • inputs.http_listener
  • inputs.http_listener_v2
• Jolokia Input
  • inputs.jolokia
  • inputs.jolokia2

Note that the two InfluxDB output plugins will remain. They are named influxdb and influxdb_v2, but in this case the version doesn't refer to the plugin but the compatible version of influxdb.

• InfluxDB Output
  • outputs.influxdb
  • outputs.influxdb_v2
• InfluxDB Listener Input
  • inputs.influxdb_listener
  • inputs.influxdb_v2_listener