How do I write script to start multiple services in centos? - hadoop

I am having multi-node cluster of Hadoop, Kafka, Zookeeper, Spark.
I am running following commands to start respective service,
$ ./Hadoop/sbin/start-all.sh
$ ./zookeeper/bin/zkServer.sh start
$ ./Kafka/Kafka-server-start.sh ./config/server-properties.sh
$ ./spark/sbin/start-all.sh
and so on..
can anyone tell me how to write a script to automate this process of running each command individually?

Have you tried creating a simple shell script with all these commands and running that script instead? For example, following is a simple bash script
#!/bin/bash
./Hadoop/sbin/start-all.sh
./zookeeper/bin/zkServer.sh start
./kafka/kafka-server-start.sh ./config/server-properties.sh
./spark/sbin/start-all.sh
and so on ...

Related

In Oozie, how I'd be able to use script output

I have to create a cron-like coordinator job and collect some logs.
/mydir/sample.sh >> /mydir/cron.log 2>&1
Can I use simple oozie wf, which I use for any shell command?
I'm asking because I've seen that there are specific workflows to execute .sh scripts
Sure, you can execute Shell action (On any node in the Yarn cluster) or use the Ssh action if you'd like to target specific hosts. You have to keep in mind that the "/mydir/cron.log" file will be created on the host the action is executed on and the generated file might no be available for other Oozie actions.

How to stop a logstash Config file running in Ubuntu?

Im running my logstash config file in Ubuntu using the following command.
/opt/logstash/bin/logstash -f /etc/logstash/conf.d/logstash.conf
Its working, However I recently realized that every time I run this command it starts another instance. Now I think there are six instances running. Because each new record i create shows as six in elasticsearch.
How can I stop all these other instances and is there any way to check how many are running?
Thanks
You can use the pkill command and specify the name of the process(es) you want to kill
pkill logstash
Or the killall command works as well the same way
killall logstash
As Val states, pkill should work to resolve what you are facing.
To avoid this in future why don't you create a small service file so which uses a PID file so you can't have multiple instances running? Here is what I did:
http://www.logstashbook.com/code/3/logstash-central.init

How is running a script using aws emr script-runner different from running it from bash?

I have used script-runner on aws emr, and given that it may look very basic (and maybe stuid) question, but I read many documents and noone answers why we need a script runner in emr, when all it does is executing a script in the master node.
Can the same script not be run using a bash?
The script runner is needed when you want to simply execute a script but the entry point is expecting a jar. For example, submitting an EMR Step will execute a "hadoop jar blah ..." command. But if "blah" is a script this will fail. Script runner becomes the jar that the Step expects and then uses its argument (path to script) to execute shell script.
When you are running your script in bash, you need to have the script locally and also you need to set all the configurations to work as you expect it.
With the script-runner you have more options, for example, run it as part of your cluster launch command, as well execute a script that is hosted remotely in S3. See the example from the EMR documentations: http://docs.aws.amazon.com/ElasticMapReduce/latest/DeveloperGuide/emr-hadoop-script.html

start multiple docker containers with a single command line shell script (without docker-compose)

I've got 3 containers that will run on a single server, which we'll call: A,B,C
Each server has a script on the host that has the commands to start docker:
A_start.sh
B_start.sh
C_start.sh
I'm trying to create a swarm script to start them all, but not sure how.
ABC_start.sh
UPDATE:
this seems to work, with the first being output to the terminal, cntrl+C exits out of them all.d
./A_start.sh & ./B_start.sh & ./C_start.sh
swarm will not help you start them at all..., it is used to distribute the work amongst docker machines that are part of the cluster.
there is no good reason not to use docker-compose for that use case, its main purpose is to link containers properly, and bring them up, so your collection of scripts could end up being a single docker-compose up command.
In bash,
you can do this:
nohup A_start.sh &
nohup B_start.sh &
nohup C_start.sh &

Simple script run via cronjob doesn't work but works from shell

I am on shared hosting and I'm trying to schedule cronjob to run every now and then. Via cPanel I scheduled to execute my script but even though that according to my host support the cronjob runs, the script doesn't seem as doing anything. The cron job command I set via cPanel is:
/bin/sh /home1/myusername/public_html/somefolder/cronjob2.sh
and the cronjob2.sh
#!/bin/bash
/home1/myusername/public_html/somefolder/node_modules/forever/bin/forever stop 0
when via SSH I execute:
/home1/myusername/public_html/somefolder/cronjob2.sh
it stops forever process as needed. From cronjob doesn't do anything.
How can I get this working?
EDIT:
So I've tried:
/bin/sh /home1/username/public_html/somefolder/cronjob2.sh >> /tmp/mylog 2>&1
and mylog entries say:
/usr/bin/env: node: No such file or directory
It seems that forever needs to run node and this cannot be found. How would I possibly fix this?
EDIT2:
Accepted answer at superuser.com. Thank you all for help
https://superuser.com/questions/763261/simple-script-run-via-cronjob-doesnt-work-but-works-from-shell/763288#763288
For cron job lines in a crontab it's not required to specify kind of shell or e.g. of perl.
It's enough, that your script contains
shebang
line.
Therefore you should remove /bin/sh from your cron job line.
Another aspect, that might cause a different behavior of your script by interactive start and by cron daemon start is possible different environment, first of all the PATH variable. Therefore check, if you script is able to be executed in very restricted environment, that is provided by cron daemon. You can determine your cron job environment experimentally by start of temporary cron job, that executes "env" command and writes its output to a file.
Once more aspect: Have you redirected STDOUT and STDERR of the cron job to a log file and read its content to analyze the issue? You can do it as follows:
your_cron_job >/tmp/any_name.log 2>&1
According to what you wrote, when you run your script via SSH, you are using bash, because this line is the first of your script:
#!/bin/bash
However, in the crontab, you are forcing the use of sh instead of bash. Are you sure your script is fully compatible with sh? Otherwise, simply replace /bin/sh with /bin/bash in your cron command and test again.

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