I wouldn't call telegraf a very good option. It does a very bad job of producing Prometheus metrics.

The best possible solution would be for FRR to support Prometheus directly, rather than require an exporter.

Timeouts and SIGKILL don't always work. If process is stuck on IO, it will not exit.

I'm not sure you understand how this works.

No, that's not the problem. The exporter itself could potentially create thousands of sub processes if something were to go wrong.

The frr_exporter linked uses os/exec to run an external binray, /usr/bin/vtysh. This is not a great way to build an exporter, as it can lead to a fork bomb. There is also the overhead of calling the external binary to gather data.

@jack9603301 Do you know of a version of that FRR exporter that doesn't fork sub processes?

We should avoid having a constellation of exporters, but favour having a single one. I feel like starting and stopping those would be pretty icky.