How to monitor a HTTP/0.9 server

[levon74]

Hi all,

Happy to join the community.

I have a piece of hardware equipment that provides an embedded HTTP telemetry that I need to monitor with Zabbix.
I have Zabbix server version 5.2.6 and it seems that the equipment's embedded web server supports only HTTP/0.9 since this is what Zabbix currently returns:

2021-08-20 12:36:37 Unsupported protocol: Received HTTP/0.9 when not allowed

When I'm trying to get the telemetry with curl I'm getting the same error message:

# curl http://10.2.8.10/monitor/temperature/temperature1
curl: (1) Received HTTP/0.9 when not allowed

If I add --http0.9 to the curl command I'm getting a proper reply:

# curl http://10.2.8.10/monitor/temperature/temperature1 --http0.9
{"temperature1": 34.69}

This is how the item is configured:

name: Temperature1
type: HTTP_AGENT
key: temp_1
applications:
-
name: Temperature
timeout: 10s
url: 'http://{HOST.IP}/monitoring/temperature/temperature1'

I tried using Web Scenarios as well, setting different client browsers but have all the same result.

Does anyone know how to make Zabbix accepting HTTP/0.9 responses if it's possible at all?
If the HTTP Agent item uses curl under the hood, is it possible to set --http0.9 somewhere manually to get Zabbix to understand v0.9 replies?

Thank you,
Levon

[Hamardaban]

Try compiling curl with http2 support.
may be it's wrong warning about unsupported protocol...

[levon74]

Hi Hamardaban,

Thanks for your response, I ended up using just an external check with a curl command and a couple of postprocessing steps.
Not the most elegant solution, but enough for now.

Cheers,
Levon