To Moloch 2.0
Read the How do I upgrade to Moloch 2.0 answer in the FAQ.
Upgrading to 2.0 takes some time, work, and requires ES 6.
To Moloch 1.5
Upgrade to Moloch 1.0 or 1.1 and finish any reindexing.
From ES 6 to ES 7
Read the How do I upgrade to ES 7 answer in the FAQ.
Installing the MaxMind DB
Read the How to install MaxMind DB answer in the FAQ.