Jason Altekruse <altekrusejason@...> writes:
>
> Hi Chris,
>
> Welcome to the drill community!
>
> What are you currently using as a VM environment? Is it running on your
own
> hardware or a cloud provider like AWS or Google Compute Engine? So far
> drill has required the nodes to be able to communicate using UDP multicast
> to sync some query information around the cluster for distributed queries.
> We realized that these providers do not support this level of network
> communication between nodes, so we have been trying to develop a
> workaround, but distributed queries will currently fail in these
> environments.
>
> If this is not the case, a look through the logs for more detailed errors
> would be the most useful for debugging your specific issue.
>
> Connecting to a specific node or a zk quorum should be the same in terms
of
> allowing execution of distributed queries, both JDBC and ODBC connections
> will run distributed queries with locality information taken into account
> where available.
>
> Distributed queries can be identified by exchanges inserted in the plan,
> this is where data is sent around to various nodes to split or merge the
> data when an operation is parallelized.
>
> -Jason Altekruse
Thanks Jason.
We're currently using vSphere on a Windows 2010 host for dev/test purposes.
The VM network is bridged onto our internal(corporate) network and we've
been told that multicast support is disabled by (corporate) default.... and
that a multicast router would be required for our subnet...
Apparently multicast support has now been enabled but our distr SQL queries
still only return data from a single Drillbit and the logs show no
communication between Drillbits... so maybe we still have a UDP multicast
issue.
I guess the next step is to find some Linux UDP test utilities and/or write
a simple Java UDP test application.
Chris
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