Logviewer ?

[yaronr]

Hi

I would like to access the storm logviewer on one of the supervisors.
How do I do that?

(AFAIK the supervisors are started by mesos)

Thanks

[brndnmtthws]

It's possible, but it's not wired up. As always, PRs are welcome.

[yaronr]

I still haven't managed to get storm to work on mesos, despite days of efforts, so first things first.. :)

[chengweiv5]

IIRC, click logviewer link from nimbus web ui will always try to connect to a constant port (8080? not for sure now), however, mesos launch supervisor in a unique and random generated directory, so the logviewer can't(maybe hack in some way) figure out where to find the correct worker's log.

[brndnmtthws]

Certainly that could be fixed.

[SEJeff]

@yaronr give me about a week to finish up and I'll post how I got it all running ontop of mesos + marathon without hardcoding the nimbus master or anything.

The gist of it is:

1. A marathon application group. One for nimbus, and one for the storm ui. The app for storm ui has a dependency on nimbus, so one starts after the other.
2. A run-storm.py which stores the actual host and port of the nimbus instance in zookeeper using the excellent Kazoo python lib.
3. run-storm.py then writes out the conf/storm.yaml with the proper nimbus.thrift.port an nimbus.host settings before launching nimbus
4. It then writes out ui.port, nimbus.host, and nimbus.thrift.port when launching storm ui.

All of this and I actually don't run it in docker, but natively under marathon, by downloading the built storm distribution and the run-storm.py via the uris flag in marathon json. I'm also chrooting this in a specific zookeeper path and having the framework name include that chroot path, so that multiple storm frameworks can run, potentially as different users, on a single mesos cluster.

In a perfect world, the framework would support a lot of this natively, but I'm a python/golang/c guy, and have never taken a serious stab at java.

[JohnOmernik]

SEJeff - Could we use something like mesos-dns to indicate where the nimbus is located? It works well for Myriad and may work well here.

[SEJeff]

It kind of defeats the point of mesos to require hard coding masters that might change. Mesos DNS is a reasonable workaround, as is my solution of having a python script write to ZK before starting nimbus and another to read from nimbus before starting storm ui.

The framework should do this natively.

[JohnOmernik]

Makes sense that the framework should do it natively, I was just suggestion the mesos-dns as a way that the nimbus/ui could be run from any node (given access to the code to run it) and where it landed wouldn't matter to the supervisors as they are pointing to a static name that resolves to a dynamic IP.

[SEJeff]

True. Thanks for the suggestion

[pdread100]

Wouldn't the most straight forward approach be to have the supervisor/executor fire up the logviewer when mesos fires it up?

If no one is working this I would like to get the logview working under mesos.

[erikdw]

I've raised an issue with how the PR #38 will handle multiple MesosSupervisors / topologies being scheduled onto the same mesos-slave host, please see: #38 (comment)

My proposal for the immediate future is to back out #38 , but I'm not sure what we should do long-term. I have some off-the-cuff thoughts here: #38 (comment)

Would appreciate others weighing in with their thoughts.

[erikdw]

I've filed a ticket against the Apache Storm project to add support for multiple container-specific logviewers: STORM-1342, thus allowing us to close PR #51.

Will require discussions with the Storm PMC type people to try to come to an acceptable design, I'm not planning on working on that in the next couple of months.