Now, another question that arises is where does Driver run? Like the executors, the driver can also run inside the cluster.
Based on where the driver is deployed, we define two deployment modes - Client and cluster.
If we are running the driver program locally, we call it client deployment mode.
If the driver is also running inside the cluster on one of the worker machines, we call it cluster deployment mode.
The diagram above shows that the driver application is running on the local machine or we are having client deployment mode. But the spark application or executors are running inside the cluster.
The example we ran earlier while discussing yarn resource manager was having client deployment mode.
If driver application shuts down the process is killed. This mode does not have resilience but it is quicker to run.
In the architecture diagram, we are running the driver inside the cluster on one of the nodes. If we are using YARN, the driver would be running inside one of the containers.
If launcher shuts down, the process continues like a batch process in background.
This is the preferred way to run the long running processes
Now, let us run the same example of computing PI in cluster mode.
Here we are first exporting the two environment variables having the hadoop's configuration directory. These variables are utlized by spark to locate the hadoop configuration and then using configuration spark figure out yarn and hdfs details.
Then we run the spark-submit with addition argument deploy-mode with value as cluster.
Now, let us run the same example of computing PI in cluster mode.
First login to Cloudxlab webconsole or login using ssh.
Then export the two variable YARN_CONF_DIR and HADOOP_CONF_DIR.
Now, lets launch the spark-submit command. Once finished, open the tracking url. When you open the tracking url, it would redirect to internal hostname. Find out the corresponding public domain name using "IP Mappings" tab of "My lab". The replace the private hostname with this hostname in the url and open. You can see that the complete details about job. Go to the "Environment" Tab and scroll down to deploy mode. You can see that the job was executed in cluster mode.
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28 Comments
Seeing error as below.Please advise
screenshot
Upvote ShareHi,
It's working fine on my end. Please use
Thanks.
Upvote ShareThe submit command does not provide any result on the console. The result like "Pi is roughly 3.1434751434751433" which used to get in local mode.
The instrcution is given - To check the status, use:
? http://e.cloudxlab.com:4040/ [4040 to be replaced by the spark port on which user is connected. In my case it is 4041. e.cloudxlab could be 'f' or some other letter. In my case it is 'f']
? http://a.cloudxlab.com:8088/cluster
What would be the status like? What is to be exactly checked and in which section of sparkUI? Image 1 and 2 depicts spark jobs and executors after execution of Yarn submit
8080 is giving error "connection time out. Please check image 3.
1. Is there a possibility (from the architecture perspective) to have a seperate machine/node for driver application in cluster mode instead of using one of the worker node?
2. Is the standalone deployment mode default since we explicitely provided 'Cluster' mode?
spark-submit --master yarn --deploy-mode cluster --class
Upvote ShareHi Punit,
It is not a good idea that the driver will run only on a specific machine/node in a production environment. If you think like this then what happens if that machine goes down, the whole system will down as there is no driver node.
So if we are using cluster mode then we also need to utilize this property as well.
Hope this helps you.
1 Upvote ShareFine thanks Vikas
Upvote ShareHI,,
I don't see the value of Pi computed in the log.
Please advise.
Hi,
Please let me know if this issue was not resolved.
Thanks.
Upvote ShareThis comment has been removed.
@Sandeep -- Sir, When running in local mode with parameters as local[5], where in the command line do you specify the worker/node on which to run the driver,assuming in this case there are 5 nodes?
Upvote ShareHi,
I ran this:
spark-submit
--master yarn --deploy-mode cluster --class
org.apache.spark.examples.SparkPi
/usr/hdp/current/spark-client/lib/spark-examples-*.jar 10
I executed successfully. But I don't see pi result (3.14whatever) in the output. What's the point ?
Hi Siddarth,
Please post full screenshot.
-- Sachin Giri
Upvote Shareexport YARN_CONF_DIR=/etc/hadoop/conf/
export HADOOP_CONF_DIR=/etc/hadoop/conf/
spark-submit --master yarn --deploy-mode cluster --class
org.apache.spark.examples.SparkPi
/usr/hdp/current/spark-client/lib/spark-examples-*.jar 10
getting error :Permission denied ?
Upvote ShareHi Team,
The video is incomplete please fix it.
Thanks
Upvote ShareHi,
Auctually the video is complete.
You need to run the below code only just to have a handson to run a job in cluster using Apache Spark.
spark-submit --master yarn --deploy-mode cluster --class org.apache.spark.examples.SparkPi /usr/hdp/current/spark-client/lib/spark-examples-*.jar 10
All the best!
vedio is incomplete!!!!
Upvote Shareplease fix it ASAP.
DIDn't expect this..
Hi,
Actually the video is complete.
You need to run the below code only just to have a handson to run a job in cluster using Apache Spark.
spark-submit --master yarn --deploy-mode cluster --class org.apache.spark.examples.SparkPi /usr/hdp/current/spark-client/lib/spark-examples-*.jar 10
All the best!
Upvote Sharespark-submit command not executing. Pl check screenshot attached. Upvote Share
Hi Sandeep,
Upvote ShareThis video is not completed, It shows only execution of commands, but final output is not displayed.
When running in cluster mode, where in the command line do you specify the worker/node on which to run the driver?
Upvote ShareHi Harry,
Good Question!
If we are running the driver on cluster, the decision is taken by cluster manager such as YARN based on the availability of resources and we don't have control over it.
So, there is no option to specify a particular node for driver while running in the cluster mode.
Upvote ShareHi Sandeep
Please configure spark to Spark 2.x version.Its now pointing to Saprk 1.5 version.
I am not able to run Spark 2 version program in cluster mode. Running spark2 in yarn mode getting below expection
java.lang.NoClassDefFoundError: com/sun/jersey/api/client/config/ClientConfig
Thanks
Upvote ShareKapil
We are working on it.
Upvote ShareThis should be rectified by now, right?
Upvote ShareHi
Upvote ShareThis video is also not proper.
I am very disappointed.
Hi Manoj,
Upvote ShareLet me into these.
Hi Manoj,
Thank you for letting us know. I have located the problem. There is a green screen.
Let me try to fix it.
Regards,
Upvote ShareSandeep Giri
This has been fixed. Thanks to you manoj.
Please let us know if you face any other problems.
Upvote Share