SNMP - Support for Textual-convention.

[framiere]

Hi,

Right now include_instances is supported which is great.
However some metrics are expressed using textual-convention.
Here is an example of such a convention

FgHaLBSchedule ::= TEXTUAL-CONVENTION
    STATUS      current
    DESCRIPTION 
        "enumerated type for HA load-balancing schedules"
    SYNTAX      INTEGER { none(1), hub(2), leastConnections(3), 
                    roundRobin(4), weightedRoundRobin(5), random(6), 
                    ipBased(7), ipPortBased(8) }

I am thinking about adding support for this feature.
Any idea/recommandation on how the configuration should look like ?

Cheers

[sparrc]

Sounds great, I don't have any opinions on how it should look because I'm not very advanced SNMP user, but if you could post some examples of a few different options you're thinking of, that would be helpful.

[phemmer]

Just fyi, with #1389 merged, the new snmp plugin supports conversion of a few different formats (see "conversion" parameter of https://github.com/influxdata/telegraf/tree/master/plugins/inputs/snmp#field-parameters).

It doesn't support all textual convention formats, as full textual convention support would be insanely complex. So I just added the most common use cases. It would be easy to add more if your use case isn't covered.

[sparrc]

this is now available in 1.0 RC 1 with the new SNMP plugin, please see here to download the latest version: https://github.com/influxdata/telegraf#linux-deb-and-rpm-packages, and the changelog for details on the new SNMP plugin.