[ClusterLabs] Coming in 1.1.15: Event-driven alerts

[Kristoffer Grönlund]

Ken Gaillot <kgaillot at redhat.com> writes:

> Hello everybody,
>
> The release cycle for 1.1.15 will be started soon (hopefully tomorrow)!
>
> The most prominent feature will be Klaus Wenninger's new implementation
> of event-driven alerts -- the ability to call scripts whenever
> interesting events occur (nodes joining/leaving, resources
> starting/stopping, etc.).

Hi, and happy to see this! Looks like a potentially very useful feature.

I started experimenting with support for alerts in crm, and have some
(very minor) nits/comments.

>
> The meta-attributes are optional properties used by the cluster.
> Currently, they include "timeout" (which defaults to 30s) and
> "tstamp_format" (which defaults to "%H:%M:%S.%06N", and is a
> microsecond-resolution timestamp provided to the alert script as the
> CRM_alert_timestamp environment variable).

Is "tstamp_format" correct? All the other meta attributes are
in-this-format, so "tstamp-format" would be preferrable to
maintain consistency. Personally, I'd prefer "timestamp-format", but
that's veering into bikeshed territory...

> In the current implementation, meta-attributes and instance attributes
> may also be specified within the <recipient> block, in which case they
> override any values specified in the <alert> block when sent to that
> recipient. Whether this stays in the final 1.1.15 release or not depends
> on whether people find this to be useful, or confusing.

Do you have any current use for this? My immediate thought is that
allowing rule expressions in the <alert> level meta and instance
attributes would be both more expressive and less confusing.

Cheers,
Kristoffer

-- 
// Kristoffer Grönlund
// kgronlund at suse.com