This could be an entire questionnaire, however, if I were an enterprise architect and needed to provide a 100,000ft view number, assuming a basic data lake to support 25 TB and grow another 25 TB (data replication factor of 3) and average workloads of several services, e.g. HDFS, Hive, HBase, and 3 master (16 core, 128 GB RAM, 2 x 2 TB) + 7 data nodes (16 cores, 256 GB RAM, 12 x 2 TB), 10 Gbps network, the cost for hardware would be anywhere between 60 and 100K. Add the cost of Hortonworks Data Subscription (check with sales rep for better number), your budget (exclude labor) would be anywhere between 100K and 150K.
Check cluster capacity planning here: http://docs.hortonworks.com/HDPDocuments/HDP2/HDP-2.4.2/bk_cluster-planning-guide/content/ch_hardwar...
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