I am totally new to Amazon Elastic MapReduce. I have a need that I want to use my custom scheduler, which is implemented based on Hadoop capacity scheduler, to schedule my jobs in Amazon Elastic MapReduce.
According to my current understanding, to achieve this, I can define only one stage in the job flow, and submit my custom jar file via SSH connection to the master node. However, I cannot find how can I edit the xml configuration files, like capacity-scheduler.xml in the master node. Anyone knows how to do that?
Moreover, if I want to add the dynamic sizing property onto it, can I dynamically tune the number of task nodes in the cluster, when the job is currently running? Or in per stage, the size of a cluster should remain the same? Thank you so much.
You should use a bootstrap action to change Hadoop configuration.
The following AWS doc can be referenced for Hadoop configuratio bootstrap action.
http://docs.aws.amazon.com/ElasticMapReduce/latest/DeveloperGuide/emr-plan-bootstrap.html#PredefinedbootstrapActions_ConfigureHadoop
This blog article that I bookmarked also has some info.
http://sujee.net/tech/articles/hadoop/amazon-emr-beyond-basics/
For changing the cluster size dynamically, one option is to use the AWS SDK.
http://docs.aws.amazon.com/ElasticMapReduce/latest/DeveloperGuide/calling-emr-with-java-sdk.html
Using the following interface you can modify the instance count of the instance group.
http://docs.aws.amazon.com/AWSJavaSDK/latest/javadoc/com/amazonaws/services/elasticmapreduce/AmazonElasticMapReduce.html
Related
Using dc/os we like to schedule tasks close to the data that the task requires that in our case is stored in hadoop/hdfs (on an HDP cluster). Issue is that the hadoop cluster is not run from within dc/os and so we are looking for a way to offer only a subset of the system resources.
For example: say we like to reserve 8GB of memory to data node services, then we like to provide the remainder to dc/os to schedule tasks.
From what i have read so far, the task can specify the resources it requires, but i have not found any means to specify what you want to offer from the node perspective.
I'm aware that a CDH cluster can be run on dc/os, that would be one way to go, but for now that is not provided for HDP.
Thanks for any idea's/tips,
Paul
After I create a google-cloud-based hadoop-enable cluster, I want to change the default bucket to a different one, how can I do that? I can't find the answer in google cloud doscumentation. Thanks!
Did you create a cluster by hand, using bdutil, using Cloud Dataproc or through some other means?
bdutil
If you used bdutil, see the choose a default file system section in the setup documentation.
Cloud Dataproc
If you used Cloud Dataproc, you can access any bucket to which your project has permission by using the gs:// uri. If you want to connect your cluster to a new bucket for logs, you will have to create a new cluster, unfortunately.
Other method
If you used a different method, like the "click to deploy" launcher, I recommend you give Dataproc or bdutil a try.
I want to find out IPs of slave nodes where currently map reduce job is running or about to run for a given Job.
Is there any method to do this ?
Thanks in Advance.
For any job, you can view the list of running tasks through the Job Scheduler Web UI - this will detail the nodes on which the task is running.
As for where tasks are about to run - this is not neccessarily decided in advance. As slots become available on a node, the Job Scheduler (there are a number which behave differently depending on your needs) identifies a job task which will run on that node (based upon a number of criteria, hopefully honoring data locality where it can) and instructs the task tracker on that node to run the specific task.
Programatically, look at the javadocs for the JobClient class, it should be able to acquire information about the running tasks, and their node names (you'll probably need to do a DNS lookup to get the actual IPs i imagine)
Hadoop comes with several web interfaces which are by default (see conf/hadoop-default.xml) available at these locations:
http://localhost:50030/ – web UI for MapReduce job tracker(s)
http://localhost:50060/ – web UI for task tracker(s)
http://localhost:50070/ – web UI for HDFS name node(s)
Thanks to #Chris..
Programatically, look at the javadocs for the JobClient class, it should be able to acquire information about the running tasks, and their node names.
I'm trying to get set up on the Amazon Cloud to run some hadoop MapReduce jobs but I'm struggling to successfully create a cluster. I have downloaded the ec2 files, have my certificates and keypair file, but I believe it's the AMIs that are causing me trouble. If I'm trying to run a cluster with a master node and n slave nodes, I start n+1 instances using standard compatible AMIs and then run the code "hadoop-ec2 launch-cluster name n" in the terminal. The master node is successful, but I get an error when the slave nodes start to launch, saying "missing parameter -h (AMI missing)" and I'm not entirely sure how to progress.
Also, some of my jobs will require an alteration in hadoops parameter settings (specifically the mapred-site.xml config file), is it possible to alter this file, and if so, how do I gain access to it? Is hadoop already installed on amazon machines, with this file accessible and alterable?
Thanks
Have you tried Amazon Elastic MapReduce? This is a simple API that brings up Hadoop clusters of a specified size on demand.
That's easier then to create own cluster manually.
But once the jobflow is finished by default it shuts the cluster down, leaving you with outputs on S3. If what you need is simply to do some crunching, this may be the way to go.
In case you need HDFS contents stored permanently (e.g. if you are running HBase on top of Hadoop) you may actually need own cluster on EC2. In this case you may find Cloudera's distribution of Hadoop for Amazon EC2 useful.
Altering Hadoop configuration on nodes it will start is possible using EC2 Bootstrap Actions:
Q: How do I configure Hadoop settings for my job flow?
The Elastic MapReduce default Hadoop configuration is appropriate for most workloads. However, based on your job flow’s specific memory and processing requirements, it may be appropriate to tune these settings. For example, if your job flow tasks are memory-intensive, you may choose to use fewer tasks per core and reduce your job tracker heap size. For this situation, a pre-defined Bootstrap Action is available to configure your job flow on startup. See the Configure Memory Intensive Bootstrap Action in the Developer’s Guide for configuration details and usage instructions. An additional predefined bootstrap action is available that allows you to customize your cluster settings to any value of your choice. See the Configure Hadoop Bootstrap Action in the Developer’s Guide for usage instructions.
About the way you are starting the cluster, please clarify:
If I'm trying to run a cluster with a master node and n slave nodes, I start n+1 instances using standard compatible AMIs and then run the code "hadoop-ec2 launch-cluster name n" in the terminal. The master node is successful, but I get an error when the slave nodes start to launch, saying "missing parameter -h (AMI missing)" and I'm not entirely sure how to progress.
How exactly you are trying start it? What exactly AMIs are you using?
Loving MRToolkit -- great to get away from Java while writing Hadoop jobs. It has become apparent that the library was written to interface with an EC2 cluster, and not with Amazon's elastic map/reduce system. Does anybody have insights into running jobs defined using the toolkit on elastic map/reduce servers? It isn't readily apparent from the web interface, and I'd love to avoid the headache of setting up a cluster by hand on EC2.
I've looked into updloading files under the 'streaming' option (as that's what MRToolkit uses), but Amazon is expecting separate files for the mapper and reducer -- typical MRToolkit style defines them in the a single file as subclasses of predefined Base(Map|Reduce) classes.
Thanks much for any thoughts.
Isaac
It's doable, but not through the web GUI.
Download and install the Ruby Client
Create your cluster: elastic-mapreduce --create --alive [params to size cluster]
Confirm your Elastic Map Reduce Master security group has port 22 open
SSH into your master node
Use git / scp to copy over your application code
Run your app