Slow changing metrics are not published to prometheus output about gnmic HOT 2 CLOSED

Hi @mathieudevos

a couple of quick comments:

1. Prometheus doesn't stoped measurements in types other than float. This usually means that you have to use a strings processor first to convert your DOWN string to 0 or 1. See an example
2. As you noted, Prometheus also doesn't quite designed to work with infrequently changed data. The effects of it is that Prometheus reports metrics to go "stale" when no data is presented to be scraped in a given (configurable) interval. This makes it challenging to use Prometheus with ON_CHANGE subscriptions for data that changes rarely.
3. There is a trick for (2) - I think it is done by setting the expiration to -1 and enabling the cache (https://gnmic.openconfig.net/user_guide/outputs/prometheus_output/#expiration) but Karim might know better

from gnmic.

Hey,

Cheers for the quick reply! For the time being I've swapped over to InfluxDB so to avoid the first issue/comment. The other ones were indeed fixed by setting the cache expiration to -1 (I believe -1s didn't work, but -1 does) and setting a cache flush timer.

I think that the final issue we're now having should be fixable if we choose to overwrite the timestamps: we'd want to get the timestamp of when the information is last read, not when it was last changed.
I'll attempt to overwrite the functionality of the timestamps.

Thank you for the quick suggestions, they've been most helpful with obtaining the data I'm looking for.

from gnmic.