Re: [Hawkular-dev] OpenShift Deployment

On Mon, Nov 27, 2017 at 4:38 PM, Matthew Wringe <mwringe(a)redhat.com&gt; wrote: > With the changes that are now going to include Prometheus, how do we want > to deploy this in OpenShift? > > We can have a few options: > > ALL-IN-ONE CONTAINER > We put both Hawkular Services and Prometheus in the same container. > > Pros: > - easy to deploy in plain docker (but this doesn't appear to be a usecase > we are targetting anyways) > - shares the same network connection (even localhost) and ip address (eg > but both services are on the different ports). > - Does't require any special wiring of components. > - Can share the same volume mount > - version of components can't get out of sync. > > Cons: > - workflow doesn't work nicely. Docker containers are meant to only run a > single application and running two can cause problems. Eg lifecycle events > would become tricky and require some hacks to get around things. > - can't independently deploy things > - can't reuse or share any existing Prometheus docker containers. > > ALL-IN-ONE POD > Hawkular Services and Prometheus are in their own containers, but they > are both deployed within the same pod. > > Pros: > - shares the same network connection. > - bound to the same machine (useful if sharing the same hostpath pv) and > don' need to worry about external network configurations (eg firewalls > between OpenShift nodes) > - pvs can be shared or separate. > - lifecycle events will work properly. > > Cons: > - lifecycle hooks will mean that both containers will have to pass before > either one will enter the ready state. So if Prometheus is failing for some > reason, Hawkular Services will not be available under the service. > - cannot independently update one container. If we need to deploy a new > container we will need to bring down the whole pod. > - are stuck with a 1:1 ratio between Hawkular Services and Prometheus > > One technical requeriment is that Hawkular Services needs to now where is Prometheus server at initialization.

I would start with this architecture first and harden the basic scenarios. > > SEPARATE PODS > Hawkular Services and Prometheus have their own separate pods. > > Pros: > - can independently run components and each component has its own > separate lifecycle > - if in the future we want to cluster Hawkular Services. this will make > it a lot easier and will also allow for running an n:m ratio between > Hawkular Services and Prometheus > - probably the more 'correct' way to deploy things as we don't have a > strong requirement for Hawkular Services and Prometheus to run together. > > Cons: > - more complex wiring. We will need to have extra services and routes > created to handle this. This mean more things running and more chances for > things to go wrong. Also more things to configure > - reusing a PV between Hawkular Services and Prometheus could be more > challenging (especially if we are using hostpath pvs). Updating the > Prometheus scrape endpoint may require a new component and container. > > _______________________________________________ > hawkular-dev mailing list > hawkular-dev(a)lists.jboss.org > https://lists.jboss.org/mailman/listinfo/hawkular-dev > >