Why hadoop commands don't work on google cloud shell - shell

After creating cluster for my project in google DataProc I've tried to type several commands for Hadoop (like hadoop fs -ls). Unfortunately it appears cloud shell doesn't see Hadoop at all!
-bash: hadoop: command not found
Someone on stackoverflow said:
"It doesn't work in Cloud Shell because it doesn't have Hadoop CLI
utilities pre-installed."
But I've no idea how to install it or either activate it. Maybe through cluster creation, but had issue with creating it through dataproc API. I've done it through cloud shell instead.
What should I do to use Hadoop commands in cloud shell properly?

apparently hadoop commands works only on VM Instances not on general project directory. So make sure you connect to cluster via Compute Engine -> VM instances -> [your node] in INSTANCES tab via SSH

Related

Issue connecting to hdfs using cloud shell

I find it quite hard accessing my hadoop data file system using google cloud shell (I’ve created a cluster on the Google Cloud Platform just to learn).
The generic ‘hdfs dfs -ls’ or ‘hadoop fs -ls gs://‘ doesn’t seem to work and I’ve been doing quite a but of trial-errors to figure out how.
Can anyone help me out on this?
Thanks :)
You can use Cloud Storage connector which provides an implementation of the FileSystem abstraction, and is available in different HDP versions, to facilitate access to GCS, and then you should be able to use 'hadoop fs -ls gs://CONFIGBUCKET/dir/file' in the hadoop shell. Please check this tutorial and also be sure that you are properly configured access to Google Cloud Storage.
The simplest way to access HDFS through Hadoop CLI is to SSH on the Dataproc cluster master node and use CLI utilities there:
gcloud compute ssh ${DATAPROC_CLUSTER_NAME}-m
hdfs dfs -ls
hadoop fs -ls gs:/
It doesn't work in Cloud Shell because it doesn't have Hadoop CLI utilities pre-installed.

Is there a way to load the install-interpreter.sh file in EMR in order to load 3rd party interpreters?

I have an Apache Zeppelin notebook running and I'm trying to load the jdbc and/or postgres interpreter to my notebook in order to write to a postgres DB from Zeppelin.
The main resource to load new interpreters here tells me to run the code below to get other interpreters:
./bin/install-interpreter.sh --all
However, when I run this command in EMR terminal, I find that the EMR cluster does not come with an install-interpreter.sh executable file.
What is the recommended path?
1. Should I find the install-interpreter.sh file and load that to the EMR cluster under ./bin/?
2. Is there an EMR configuration on start time that would enable the install-interpreter.sh file?
Currently all tutorials and documentations assumes that you can run the install-interpreter.sh file.
The solution is to not run this code below in root (aka - ./ )
./bin/install-interpreter.sh --all
Instead in EMR, run the code above in Zeppelin, which in the EMR cluster, is in /usr/lib/zeppelin

start-all.sh command not found

I have just installed Cloudera VM setup for hadoop. But when I open the command prompt and want to start all daemons for hadoop using command 'start-all.sh' , I get an error stating "bash : start-all.sh: command not found".
I have tried 'start-dfs.sh' too yet still gives the same error. When I use 'jps' command, I can see that none of the daemons have been started.
You can find start-all.sh and start-dfs.sh scripts in bin or sbin folders. You can use the following command to find that. Go to hadoop installation folder and run this command.
find . -name 'start-all.sh' # Finds files having name similar to start-all.sh
Then you can specify the path to start all the daemons using bash /path/to/start-all.sh
If you're using the QuickStart VM then the right way to start the cluster (as #cricket_007 hinted) is by restarting it in the Cloudera Manager UI. The start-all.sh scripts will not work since those only apply to the Hadoop servers (Name Node, Data Node, Resource Manager, Node Manager ...) but not all the services in the ecosystem (like Hive, Impala, Spark, Oozie, Hue ...).
You can refer to the YouTube video and the official documentation Starting, Stopping, Refreshing, and Restarting a Cluster

Hadoop cluster configuration with Ubuntu Master and Windows slave

Hi I am new to Hadoop.
Hadoop Version (2.2.0)
Goals:
Setup Hadoop standalone - Ubuntu 12 (Completed)
Setup Hadoop standalone - Windows 7 (cygwin being used for only sshd) (Completed)
Setup cluster with Ubuntu Master and Windows 7 slave (This is mostly for learning purposes and setting up a env for development) (Stuck)
Setup in relationship with the questions below:
Master running on Ubuntu with hadoop 2.2.0
Slaves running on Windows 7 with a self compiled version from hadoop 2.2.0 source. I am using cygwin only for the sshd
password less login setup and i am able to login both ways using ssh
from outside hadoop. Since my Ubuntu and Windows machine have
different usernames I have set up a config file in the .ssh folder
which maps Hosts with users
Questions:
In a cluster does the username in the master need to be same as in the slave. The reason I am asking this is that post configuration of the cluster when I try to use start-dfs.sh the logs say that they are able to ssh into the slave nodes but were not able to find the location "/home/xxx/hadoop/bin/hadoop-daemon.sh" in the slave. The "xxx" is my master username and not the slaveone. Also since my slave in pure Windows version the install is under C:/hadoop/... Does the master look at the env variable $HADOOP_HOME to check where the install is in the slave? Is there any other env variables that I need to set?
My goal was to use the Windows hadoop build on slave since hadoop is officially supporting windows now. But is it better to run the Linux build under cygwin to accomplish this. The question comes since I am seeing that the start-dfs.sh is trying to execute hadoop-daemon.sh and not some *.cmd.
If this setup works out in future, a possible question that I have is whether Pig, Mahout etc will run in this kind of a setup as I have not seen a build of Pig, Mahout for Windows. Does these components need to be present only on the master node or do they need to be in the slave nodes too. I saw 2 ways of running mahout when experimenting with standalone mode first using the mahout script which I was able to use in linux and second using the yarn jar command where I passed in the mahout jar while using the windows version. In the case Mahout/ Pig (when using the provided sh script) will assume that the slaves already have the jars in place then the Ubuntu + Windows combo does not seem to work. Please advice.
As I mentioned this is more as an experiment rather than an implementation plan. Our final env will be completely on linux. Thank you for your suggestions.
You may have more success going with more standard ways of deploying hadoop. Try out using ubuntu vm's for master and slaves.
You can also try to do a pseudo-distributed deployment in which all of the processes run on a single VM and thus avoid the need to even consider multiple os's.
I have only worked with the same username. In general SSH allows to login with a different login name with the -l command. But this might get tricky. You have to list your slaves in the slaves file.
At least at the manual https://hadoop.apache.org/docs/r0.19.1/cluster_setup.html#Slaves I did not find anything to add usernames. it might be worth trying to add -l login_name to the slavenode in the slave conf file and see if it works.

hadoop cluster clarification

I am a newbie in hadoop and I am trying to run a hadoop jar on Amazon EC2. I have started my amazon ec2 instance through the console, uploaded my files to the dfs and then was able to successfully run the job jar and generate output on the instance.
But still I am confused on one part. I am not sure if the job was run on a single machine in amazon ec2 or was it ran on a cluster? How do I find the number of worker nodes involved for my jar run?
In some reference links I see we have to use launch-cluster command , for example "bin/hadoop-ec2 launch-cluster test-cluster 2" . What is the difference in starting the instance from the console and using this command like launch-cluster.

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