I have created a Spark HDInsight Cluster on Azure. The cluster was used to run different jobs (either Spark or Hive).
Until a month ago, the history of the jobs could be seen in the Spark History Server dashboard. It seems that following the update that introduced Spark 1.6.0, this dashboard is no longer showing any applications.
I have also tried to bypass this issue by executing the PowerShell cmdlet for get-azurehdinsightjob as sugested here. The output is again an empty list of applications.
I would appreciate any help as this dashboard used to work and now all my experiments are stalled.
I managed to solve the issue by deleting everything inside wasb:///hdp/spark-events. Maybe the issue was related to the size of the folder, as no other log files could be appended.
All the following jobs are now appearing successfully in the Spark History Server dashboard.
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A peer of mine has created code that opens a restful api web service within an interactive spark job. The intent of our company is to use his code as a means of extracting data from various datasources. He can get it to work on his machine with a local instance of spark. He insists that this is a good idea and it is my job as DevOps to implement it with Azure Databricks.
As I understand it interactive jobs are for one-time analytics inquiries and for the development of non-interactive jobs to be run solely as ETL/ELT work between data sources. There is of course the added problem of determining the endpoint for the service binding within the spark cluster.
But I'm new to spark and I have scarcely delved into the mountain of documentation that exists for all the implementations of spark. Is what he's trying to do a good idea? Is it even possible?
The web-service would need to act as a Spark Driver. Just like you'd run spark-shell, run some commands , and then use collect() methods to bring all data to be shown in the local environment, that all runs in a singular JVM environment. It would submit executors to a remote Spark cluster, then bring the data back over the network. Apache Livy is one existing implementation for a REST Spark submission server.
It can be done, but depending on the process, it would be very asynchronous, and it is not suggested for large datasets, which Spark is meant for. Depending on the data that you need (e.g. highly using SparkSQL), it'd be better to query a database directly.
I'm currently using databricks and in order to test my databricks code I'm using databricks connect in VS code. While I'm using databricks connect, since yesterday suddenly it started behaving strange, while I'm submitting a code from VS Code, the databricks-connect is taking the access of the person who has created the databricks cluster, now he doesn't have adequate access over all the resources and my test cases/ code is failing due to access issue.
Some more inputs: I have a function which does an update operation in a delta table, so this means i can't use a normal hive or temp table as they doesn't support update operation.
I have tried delta-lake in local, but that seems tobe not working and also not that convenient, as i wouldn't be able to access my ADLs location (until i specifically do the configuration change)
So, mu question is , how you guys are doing a spark specific testing? (I'm using pytest).
I found we don't have much material for a databricks code testing in the internet..any help?
I want to install Apache Spark v2.4 on my Kubernetes cluster, but there does not seem to be a stable helm chart for this version. An older/stable chart (for v1.5.1) exists at
https://github.com/helm/charts/tree/master/stable/spark
How can I create/find a v2.4 chart?
Then: The reason for needing v2.4 is to enable client-mode, because I would like to be able to submit (PySpark/Jupyter notebook) jobs to the cluster from my laptop's dev environment. What extra steps are required to enable client-mode (including exposing the service)?
The closest attempt so far (but for Spark v2.0.0) that I have found, but which I haven't yet got working, is at
https://github.com/Uninett/kubernetes-apps/tree/master/spark
At https://github.com/phatak-dev/kubernetes-spark (also two years old), there is nothing about jupyter deployment.
Pangeo-specific: https://discourse.jupyter.org/t/spark-integration-documentation/243
SO thread: https://github.com/jupyterhub/zero-to-jupyterhub-k8s/issues/1030
I have searched for up-to-date resources on this but have found nothing that has everything in one place. I will update this question with other relevant links if and when people are able to point them out to me. Hopefully it will be possible to cobble together an answer.
As ever, huge thanks in advance.
Update:
https://github.com/SnappyDataInc/spark-on-k8s for v2.2 is extremely easy to deploy - looks promising...
see https://hub.helm.sh/charts/microsoft/spark this is based off https://github.com/helm/charts/tree/master/stable/spark and uses spark 2.4.6 with hadoop 3.1. You can check the source for this chat at https://github.com/dbanda/charts. The Livy service makes it easy to submit spark jobs via REST API. You can also submit jobs using Zeppelin. We made this chart as alternative way to run spark on K8s without using the spark-submit k8s mode. I hope it helps.
I created a cluster in Google Cloud and submitted a spark job. Then I connected to the UI following these instructions: I created an ssh tunnel and used it to open the Hadoop web interface. But the job is not showing up.
Some extra information:
If I connect to the master node of the cluster via ssh and run spark-shell, this "job" does show up in the hadoop web interface.
I'm pretty sure I did this before and I could see my jobs (both running and already finished). I don't know what happened in between for them to stop appearing.
The problem was that I was running my jobs in local mode. My code had a .master("local[*]") that was causing this. After removing it, the jobs showed up in the Hadoop UI as before.
Every few days the Azure HDInsight cluster is being (randomly?) restarted by Microsoft, and in the process any custom changes to hive-site.xml (such as adding a JsonSerde) are lost without any prior warning, and as a result the hive queries from Excel/PowerPivot starts breaking.
How are you supposed to deal with this scenario - are we forced to store our data as CSV files ?
In order to preserve customization during os update or node re-image, you should think of using script action. Here is the link: http://azure.microsoft.com/en-us/documentation/articles/hdinsight-hadoop-customize-cluster/
If you specify the Hive config parameter with a custom configuration object at the time of cluster creation, it should persist. The link here http://hadoopsdk.codeplex.com/wikipage?title=PowerShell%20Cmdlets%20for%20Cluster%20Management has some more details on creating a cluster with custom configuration.
This blog post on MSDN has a table showing what customizations are supported via the different methods, as well as examples for using PowerShell or the SDK to create a cluster with custom Hive configuration parameters (Line 62-64 in the Powershell example): http://blogs.msdn.com/b/bigdatasupport/archive/2014/04/15/customizing-hdinsight-cluster-provisioning-via-powershell-and-net-sdk.aspx
This is the only way to persist these settings because the cluster nodes can be reset for Azure servicing events such as security updates, and the configurations are set back to the initial values when this occurs.