Cedric H.'s questions

The X-pack package from Elastic is fully integrated with Elasticsearch and Kibana to provide (among other things) an alarm reporting platform.

I believe that the regular use case is to build that from Kibana, with alarms as the results of particular queries.

I want to use that, but I'm also considering to use it as the alarm infrastructure for my complete platform: that means that an application wanting to send an alarm, would for example write explicitely the message in ES and an alarm would be generated.

Is this stupid, am I missing something?

I have an industrial system producing log files where some of the lines look like this:

component1 v1 component2 v2 component3 v3 ...

Where vx is a numerical value (eg. 3.14159).

I'm running a super basic ELK stack and I would like to extract these as field/value.

I don't know how/where to attack the problem. Is that a logstash configuration that should be done to extract fields from single lines ?

Considering Docker 1.12. I understand that volumes are not per say portable across the swarm and that solutions like Flocker would be better for larger clusters.

Nevertheless, is the option I describe below acceptable for my setup?

Setup A swarm with 3 nodes runnin Docker 1.12.latest from the experimental branch.

Goal Run a nice but small Cassandra cluster.

Problem I want to decouple the stateful part of the service (the data volume) from the stateless Cassandra daemons.

Proposed solution Create a named volume manually on each node with the same name on each node. Use docker service create --name cassandra --replicas 3 --mount type=volume,source=cassandra_data,target=/usr/var/cassandra

My understanding is that one replica of the Cassandra will be run and every node, each one referring a local named volume with the same name.

Would this work? Do I need to specify a constraint to make sure there is at max 1 replica per node of the swarm?

Edit: reading the doc, it seems I should use --mode=global instead of replicas=3 to run exactly 1 replica per node of the swarm. Which makes a lot of sense...

Is it possible to force a yum installation despite missing dependencies?

I know it is possible to do that with rpm but so far I couldn't find any yum magic.