These topics can be quite involved, I am going to err on the pithy side....
1. A CDH -> HDP
migration can either be a cluster takeover or a Cluster to New Cluster
migration. A takeover can be similar to
a HDP X to HDP Y upgrade.
Distcp is often used for a
Cluster -> New Cluster migration.
2. Hive, Pig, et al
should work in the same manner as CDH and HDP – assuming you are migrating to
the
same version, or a backward
compatible version. Hive and Pig are not tied to one distro.
3. HDP is installed
with a complete set of site files managed by default by Ambari. If there are
customized parameters,
or CDH specifics, I would use
a compare tool (diff, etc.) to examine the differences between HDP and CDH.
HDP will also provide a
guided configuration (i.e. tuning recommendations). Better to start with the
HDP guided
configs, check the differences,
and apply them in a controlled manner.
4. Ranger is less
likely to be part of a CDH distro. Ranger is part of HDP by default. Policies
are stored in the Ranger DB.
Should work if they are
defined on Open components. Would advise testing, etc. Keep in mind there are
many options
to do some quick tests – HDP Sandbox,
HDC in AWS, HDP in Azure, etc.
Would also advise you understand the use cases/workloads/data on your existing cluster, and ensure you map to the same functionality in HDP. Usually many of the components are the same (i.e. HBase, Hive, Spark).
