Writting MQTT with SSL messages to Influxdb

Telegraf
1

Hi all,

My Mosquitto MQTT server is using SSL and I am not able to find any examples on how to write MQTT to Influxdb when you have a MQTT using SSL. Can someone please provide a full example?

This is the link to the conf file telegraf/telegraf.conf at 2f8d0f4d4784f1ee217bce2c40c94b1dd78bd908 · influxdata/telegraf · GitHub

Thank you.

2

It appears that you must have one of the ssl options set or the insecure_skip_verify must be true to enable SSL. I’ll open an issue on the issue tracker but in the meantime can you set insecure_skip_verify = true?

3

I will include a fix in the next patch release so you can specify the protocol in the servers URL. Keep an eye on this pull request for updates.

4

Hi Daniel,

Thank you for your reply. I am new to this, so I just want to make sure. Do I use the MQTT cert or the telegraf cert. I’ve added a sample below.

servers = [“mqtt domain name:8883”]
qos = 0
topics = [
“iotdevices/+/#”,
]
client_id = "deviceCollection"
username = "user"
password = "pass"
data_format = "value"
data_type = “int”

–which cert do I use?
ssl_ca = “/mqtt-ca.cert” or ssl_ca = "/telegraf-ca.crt"
insecure_skip_verify = true

Thank you.

5

It should switch over to using ssl just by having insecure_skip_verify = true set, this disables cert verification so I think there is no purpose to also setting the ssl_ca. To answer your question though, use mqtt-ca.cert, the ssl_ca is the certificate for the key that has signed the MQTT certificate.

6

Thank you for the explanation, I have followed your instruction but keep getting different errors every time I restart the Telegraf service or reboot. No changes was made to the file when restarting.

Each line is a different restart or reboot:
E! Error parsing /etc/telegraf/telegraf.conf, line 2515: field corresponding to servers' is not defined in*system.SystemStats’
E! Error parsing /etc/telegraf/telegraf.conf, line 2546: field corresponding to data_format' is not defined in*system.SystemStats’
E! Error parsing /etc/telegraf/telegraf.conf, line 2519: field corresponding to connection_timeout' is not defined in*system.SystemStats’
E! Error parsing /etc/telegraf/telegraf.conf, line 2517: field corresponding to qos' is not defined in*system.SystemStats’

Here are the settings from the Telegraf.conf file:

servers = “mqtt-domain-name:8883”
qos = 0
topics = “iotdevices/+/#”
client_id = "deviceCollection"
username = "user"
password = "pass"
data_format = "value"
data_type = “int”
ssl_ca = "/ect/ssl//mqtt-ca.crt"
insecure_skip_verify = true

The errors are very strange, any thoughts?

7

I think you might be missing the plugin table: [[inputs.mqtt_consumer]].

8

Ok, I see what I did wrong. I forgot to uncomment the plugin table, here is the working settings.

[[inputs.mqtt_consumer]]
servers = [“mqtt-domain-name:8883”]
qos = 0
topics = [“iotdevices/+/#”]
client_id = "deviceCollection"
username = "user"
password = "pass"
data_format = "value"
data_type = “int”
ssl_ca = "/ect/ssl//mqtt-ca.crt"
insecure_skip_verify = true

I checked the logs and it looks like it’s working. Thank you so much for you help Daniel.
One more question, is there a way to make the error logs a bit more specific?

Thank you again.

9

I’m working on rewriting the configuration system, I’ll see what if I can do to improve the error message here a bit.

10

Great! and thank you again for your help.