Install Telegraf from this official site: https://www.influxdata.com/get-telegraf/

For Ubunbu:
  - after install, edit conf file in /etc/telegraf/telegraf.conf
  - test the conf by:  telegraf --config /etc/telegraf/telegraf.conf --test
  - start the service: sudo systemctl restart telegraf

For Windows:
  - after install, edit the conf file in where telegraf was extracted
  - install telegraf as a service (follow the instruction)
  - test conf via powershell: & "C:\Program Files\Telegraf\telegraf.exe" --config "C:\Program Files\Telegraf\telegraf.conf"
  - start the service from Windows service

Sample working conf:
<code>
[agent]
  interval = "1s"          # Frequent checks for internal housekeeping
  flush_interval = "1s"    # Push to MySQL every 1 second (or as soon as data exists)
  flush_jitter = "0s"      # Ensure no random delay in flushing
  precision = "1ms"        # High-precision timestamps
  debug = true
  omit_hostname = true

# ------------------------------------------------------------------------------
# INPUTS
# ------------------------------------------------------------------------------

# Input 1: Alerts
[[inputs.mqtt_consumer]]
  servers = ["tcp://localhost:1883"]
  topics = ["grocery/fdas/alerts"]
  name_override = "sbifdas_alerts" # Unique name for internal routing
  data_format = "json"    
  json_string_fields = ["desc"]
  tagexclude = ["topic", "host"]

# Input 2: Response
[[inputs.mqtt_consumer]]
  servers = ["tcp://localhost:1883"]
  topics = ["grocery/fdas/response"] 
  name_override = "sbifdas_response" # Unique name for internal routing
  data_format = "json"
  tagexclude = ["topic", "host", "measurement"]
  fieldexclude = ["ip"]

# ------------------------------------------------------------------------------
# PROCESSORS
# ------------------------------------------------------------------------------

# Applies only to the Alerts input
[[processors.rename]]
  namepass = ["sbifdas_alerts"]
  [[processors.rename.replace]]
    field = "desc"
    dest = "name"
  [[processors.rename.replace]]
    field = "id"
    dest = "senderid"    

# Applies only to the Response input
[[processors.unpivot]]
  namepass = ["sbifdas_response"]
  tag_key = "name"
  value_key = "val"
  
[[processors.strings]]
  # This targets the text inside the fields/tags named "name" and "senderid"
  [[processors.strings.uppercase]]
    field = "name"
  [[processors.strings.uppercase]]
    tag = "name"
  [[processors.strings.uppercase]]
    field = "senderid"
  [[processors.strings.uppercase]]
    tag = "senderid"

# Applies only to the Response input (after unpivot)
[[processors.template]]
  namepass = ["sbifdas_response"]
  tag = "senderid"
  template = "{{ .Tag \"name\" }}"

# Final Rename: Both inputs are renamed to match your SQL table name
[[processors.rename]]
  [[processors.rename.replace]]
    measurement = "sbifdas_alerts"
    dest = "sbifdas"
  [[processors.rename.replace]]
    measurement = "sbifdas_response"
    dest = "sbifdas"
	
	

# ------------------------------------------------------------------------------
# OUTPUTS
# ------------------------------------------------------------------------------

[[outputs.sql]]
  driver = "mysql"
  data_source_name = "iottest:iottester@tcp(localhost:3306)/iot?sql_mode=ANSI_QUOTES&time_zone='%2B08:00'"
  timestamp_column = "dummy"
  fieldinclude = ["senderid", "name", "val"]
  taginclude = []
</code>