Sources of information

You don't just need new technologies and tools, no matter how cool they are. Sometimes, a little help from a more experienced source can pull you out of a hole. In this regard you are well covered; the Hadoop community is extremely strong in many areas.

Source code

It's sometimes easy to overlook, but Hadoop and all the other Apache projects are after all fully open source. The actual source code is the ultimate source (pardon the pun) of information about how the system works. Becoming familiar with the source and tracing through some of the functionality can be hugely informative, not to mention helpful, when you hit unexpected behavior.

Mailing lists and forums

Almost all the projects and services listed earlier have their own mailing lists and/or forums; check out the homepages for the specific links. If using AWS, make sure to check out the AWS developer forums at https://forums.aws.amazon.com.

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