--- title: Spark in Kubernetes with OzoneFS menu: main: parent: Recipes --- Using Ozone from Apache Spark === This recipe shows how Ozone object store can be used from Spark using: - OzoneFS (Hadoop compatible file system) - Hadoop 2.7 (included in the Spark distribution) - Kubernetes Spark scheduler - Local spark client ## Requirements Download latest Spark and Ozone distribution and extract them. This method is tested with the `spark-2.4.0-bin-hadoop2.7` distribution. You also need the following: * A container repository to push and pull the spark+ozone images. (In this recipe we will use the dockerhub) * A repo/name for the custom containers (in this recipe _myrepo/ozone-spark_) * A dedicated namespace in kubernetes (we use _yournamespace_ in this recipe) ## Create the docker image for drivers ### Create the base Spark driver/executor image First of all create a docker image with the Spark image creator. Execute the following from the Spark distribution ``` ./bin/docker-image-tool.sh -r myrepo -t 2.4.0 build ``` _Note_: if you use Minikube add the `-m` flag to use the docker daemon of the Minikube image: ``` ./bin/docker-image-tool.sh -m -r myrepo -t 2.4.0 build ``` `./bin/docker-image-tool.sh` is an official Spark tool to create container images and this step will create multiple Spark container images with the name _myrepo/spark_. The first container will be used as a base container in the following steps. ### Customize the docker image Create a new directory for customizing the created docker image. Copy the `ozone-site.xml` from the cluster: ``` kubectl cp om-0:/opt/hadoop/etc/hadoop/ozone-site.xml . ``` And create a custom `core-site.xml`: ``` fs.o3fs.impl org.apache.hadoop.fs.ozone.BasicOzoneFileSystem ``` _Note_: You may also use `org.apache.hadoop.fs.ozone.OzoneFileSystem` without the `Basic` prefix. The `Basic` version doesn't support FS statistics and encryption zones but can work together with older hadoop versions. Copy the `ozonefs.jar` file from an ozone distribution (__use the legacy version!__) ``` kubectl cp om-0:/opt/hadoop/share/ozone/lib/hadoop-ozone-filesystem-lib-legacy-0.4.0-SNAPSHOT.jar . ``` Create a new Dockerfile and build the image: ``` FROM myrepo/spark:2.4.0 ADD core-site.xml /opt/hadoop/conf/core-site.xml ADD ozone-site.xml /opt/hadoop/conf/ozone-site.xml ENV HADOOP_CONF_DIR=/opt/hadoop/conf ENV SPARK_EXTRA_CLASSPATH=/opt/hadoop/conf ADD hadoop-ozone-filesystem-lib-legacy-0.4.0-SNAPSHOT.jar /opt/hadoop-ozone-filesystem-lib-legacy.jar ``` ``` docker build -t myrepo/spark-ozone ``` For remote kubernetes cluster you may need to push it: ``` docker push myrepo/spark-ozone ``` ## Create a bucket and identify the ozonefs path Download any text file and put it to the `/tmp/alice.txt` first. ``` kubectl port-forward s3g-0 9878:9878 aws s3api --endpoint http://localhost:9878 create-bucket --bucket=test aws s3api --endpoint http://localhost:9878 put-object --bucket test --key alice.txt --body /tmp/alice.txt kubectl exec -it scm-0 ozone s3 path test ``` The output of the last command is something like this: ``` Volume name for S3Bucket is : s3asdlkjqiskjdsks Ozone FileSystem Uri is : o3fs://test.s3asdlkjqiskjdsks ``` Write down the ozone filesystem uri as it should be used with the spark-submit command. ## Create service account to use ``` kubectl create serviceaccount spark -n yournamespace kubectl create clusterrolebinding spark-role --clusterrole=edit --serviceaccount=yournamespace:spark --namespace=yournamespace ``` ## Execute the job Execute the following spark-submit command, but change at least the following values: * the kubernetes master url (you can check your ~/.kube/config to find the actual value) * the kubernetes namespace (yournamespace in this example) * serviceAccountName (you can use the _spark_ value if you folllowed the previous steps) * container.image (in this example this is myrepo/spark-ozone. This is pushed to the registry in the previous steps) * location of the input file (o3fs://...), use the string which is identified earlier with the `ozone s3 path ` command ``` bin/spark-submit \ --master k8s://https://kubernetes:6443 \ --deploy-mode cluster \ --name spark-word-count \ --class org.apache.spark.examples.JavaWordCount \ --conf spark.executor.instances=1 \ --conf spark.kubernetes.namespace=yournamespace \ --conf spark.kubernetes.authenticate.driver.serviceAccountName=spark \ --conf spark.kubernetes.container.image=myrepo/spark-ozone \ --conf spark.kubernetes.container.image.pullPolicy=Always \ --jars /opt/hadoop-ozone-filesystem-lib-legacy.jar \ local:///opt/spark/examples/jars/spark-examples_2.11-2.4.0.jar \ o3fs://bucket.volume/alice.txt ``` Check the available `spark-word-count-...` pods with `kubectl get pod` Check the output of the calculation with `kubectl logs spark-word-count-1549973913699-driver` You should see the output of the wordcount job. For example: ``` ... name: 8 William: 3 this,': 1 SOUP!': 1 `Silence: 1 `Mine: 1 ordered.: 1 considering: 3 muttering: 3 candle: 2 ... ```