Dhive

The aim of this proyect is to make it easy to deploy a kerberized stack of hadoop/yarn/tez/hive.

Configure Docker networking

All the services start in Docker containers which are deployed with docker-compose so both have to be installed Hadoop requires reverse DNS. Under docker-compose, we require an external network named "com" for hosts to resolve forward and backwards.

docker network create com

Probably it's convenient to allow docker more memory/core resources than the defaults.

Getting started

Python3 has to be installed. To install the requirements:

python -m pip install -r requirements.txt

Running:

make all

This will:

• Start several services in docker images: kerberos, hadoop, yarn, tez, hive or other services depending on what's defined on config/vars.cfg
• Pull relevant logs from the docker images which can be seen at http:localhost:8123

The file config/vars.cfg holds the values for:

• The version values for hadoop, hive, tez.
• The services that will be running.
• Properties that will be overriden for core-site.xml, hdfs-site.xml, yarn-site.xml, tez-site.xml and hive-site.xml.

To tear down everything:

make clean

Using a local hive or tez distribution

This can be enabled by setting the variables hive_path or tez_path in config/vars.cfg. If we want dhive to also compile and push the generated tar to the docker containers the variables HIVE_COMPILE and TEZ_COMPILE have to be set to 1, for example:

HIVE_COMPILE=1 make clean all

If hive_path or tez_path are not set dhive will download the release from the version specified in config/vars.cfg. If won't download it again if it's on the root directory. If hive_path or tez_path are set dhive but not HIVE_COMPILE or TEZ_COMPILE it won't compile the source code but it will still try to get the tarball from the path.

If some changes are made (changes to config/vars.cfg or to the source code) and we want to redeploy hive/tez/ranger nodes we can do:

make restart-{hive|tez|ranger}

If we want to recompile because a change in the source code has been done:

HIVE_COMPILE=1 make restart-{hive|tez|ranger}

In this case the version should be set to the compiled version which would be something like hive_version = 4.0.0-SNAPSHOT or tez_version = 0.10.0-SNAPSHOT.

Run commands in containers

We can do this from any running container:

docker exec -it nn.example /bin/bash
kinit -kt /var/keytabs/hdfs.keytab hdfs/nn.example.com
hdfs dfs -ls /

If hive is running (with kerberos) we can get a beeline prompt:

docker exec -it hs2.example /bin/bash
kinit -kt /var/keytabs/hdfs.keytab hive/hs2.example.com
beeline -u "jdbc:hive2://hs2.example.com:10000/;principal=hive/hs2.example.com@EXAMPLE.COM;hive.server2.proxy.user=hive/hs2.example.com@EXAMPLE.COM"

# For example now to activate the whole stack:
jdbc:hive2://hs2.example.com:10000/>CREATE TABLE pokes (foo INT, bar STRING);
jdbc:hive2://hs2.example.com:10000/>INSERT INTO pokes VALUES (1, "1");
jdbc:hive2://hs2.example.com:10000/>SELECT * from pokes;

Running a different .cfg file

By default config/vars.cfg will be used but other configurations are available in the config folder. They can be run setting the DHIVE_CONFIG_FILE environment variable, for example:

DHIVE_CONFIG_FILE=config/external/spark.cfg make clean all
HIVE_COMPILE=1 DHIVE_CONFIG_FILE=config/external/spark.cfg make restart-hive-server

are valid commands. To see what services a particular configuration file is going to deploy the easiest way to see it is to check the [services] section in the file.

Adding services

Usually the following steps would be taken:

• Add a new SERVICE_NAME.yml to dhive/services.
• Maybe adding a start script to dhive/containers/base/docker_scripts.
• Maybe creating a new principal in dhive/containers/base/docker-scripts/start-kdc.sh.
• Maybe overriding or removing some of the properties of the configuration files.
• Add the new service to config/vars.cfg or to a different configuration file (it can be set with the environment variable DHIVE_CONFIG_FILE).

An example of this is adding a mysql backend for the hivemetastore. It can be run with:

DHIVE_CONFIG_FILE=config/mysql.cfg make all

Running a container with a job

This can be done to submit a jar to hadoop to run with tez, or to run hive queries, or more generally, once the environment is set up, to take actions against it. An example of how the first would be done is the file config/external/run_tez_job.cfg. It's added like another service but it has to start with external. Four variables are defined inside the service section:

• docker: instructions to add to the Dockerfile.
• assure: files to copy to the folder where docker is going to be built.
• run: script to run inside the container.
• kerberos: principals to add for kerberos at the running host.

To run this particular example: DHIVE_CONFIG_FILE=config/external/run_tez_job.cfg make all

This will also generate the script build/restart-new-service-name in case we want to tweak something in the .cfg file and only restart the new service.

LLAP

LLAP can be deployed with the config file config/llap.cfg.

Ranger

Ranger can be deployed and integrated with hive with the config file config/ranger.cfg.

AWS

Sample configuration that show how write tables in s3 can be found in config/aws.cfg.

Spark

An example of how to run a spark job against hive is shown in config/external/spark.cfg. In a similar way it can be done against a LLAP setup.

How it works

The folder dhive is formed by the templates. When running:

make generate

the real files that will deploy the containers are generated under build. This accomplishes being able to use global variables across all the files and being able to override the properties specified in config/vars.cfg for the configuration files.