Filter out devices with port type other than FIBRE (e.g. twisted pair ports)

[kandrew]

On systems where there are active twisted pair ports (e.g. a management 1g connection) this exporter produces a ton of messages in the dmesg that are coming from the driver:

[58543.598848] i40e 0000:03:00.0 lan0: Module type unrecognized
[58597.231908] i40e 0000:03:00.0 lan0: Module type unrecognized
[58603.599266] i40e 0000:03:00.0 lan0: Module type unrecognized
[58657.231980] i40e 0000:03:00.0 lan0: Module type unrecognized

And if you check the port type it's a twisted pair:

> sudo ethtool lan0 | grep 'Port:'
        Port: Twisted Pair
>

It's possible to exclude this via regex, but there is no reason this exporter shouldn't do this automatically.

[loulecrivain]

Hello @kandrew,
Thank you for the report, it's appreciated! We don't have the same environment, so it's nice to have feedback from other users.

We'll see what we can do.

[Kek5chen]

I'm not sure but I think this is an upstream issue in https://github.com/wobcom/go-ethtool.