Documentation for creating new entry in `generator.yml` file

[francois09]

Hi,

Using a Debian 12 out-of-the-box prometheus-snmp-exporter package:

$ prometheus-snmp-exporter --version
snmp_exporter, version 0.21.0 (branch: debian/sid, revision: 0.21.0-1+b5)
build user: team+pkg-go@tracker.debian.org
build date: 20230409-10:16:26
go version: go1.19.8
platform: linux/amd64

I'm trying to collect informations from a TrendNet Wifi access point (TEW-740APBO) with MIB on https://downloads.trendnet.com/TEW-740APBO/MIB/, but using curl 'localhost:9116/snmp?target=192.168.54.253' return the following error:

An error has occurred while serving metrics:

error collecting metric Desc{fqName: "snmp_error", help: "Error scraping target", constLabels: {}, variableLabels: []}: error getting target 192.168.54.253: request timeout (after 3 retries)

The snmpwalk -v 2c -c public_v2 192.168.54.253 command return correct OID values.

I imagine I've to create a specific module in generator.yml file, but I don't know where to start. Maybe I'm wrong, so any advice is welcome.

Thanks for the job done, this exporter works really fine with my Ubiquiti Edge-5 router !