I have an Amazon EC2 instance running my website. I need to setup a Cron Job to run my file every 12hours.
if file setup via command line so please give a detail step wise.
Does anyone have any advise?
Thanks for your time.
I recently began using Amazon's linux distro on ec2 instances and after trying all kinds of things for cron all I needed was:
sudo service crond start
crontab -e
This allowed me to set a cron job as "ec2-user" without specifying the user. For example:
0 12 * * * python3 example.py
In fact, specifying a user here prevented it from running. I also posted this here.
It's just normal cron.
See: HowTo: Add Jobs To cron Under Linux or UNIX?
Related
I have got an assignment. The assignment is "Write a shell script to install and configure docker swarm(one master/leader and one node) and automate the process using Jenkins." I am new to this technology and finding it difficult to proceed. Can anyone help me in explaining step-by-step process of how to proceed?
#Rajnish Kumar Singh, Have you tried to check resources online? I understand you are very new to this technology, but googling some key words like
what is docker swarm
what is jenkins , etc would definitely helps
Having said that, Basically you need to do below set of steps to complete your assignment
Pre-requisites
2 or more - Ubuntu 20.04 Server
(You can use any linux distros like ubuntu, Redhat etc, But make sure your install and execute commands change accordingly.
Here we need two nodes mainly to configure the master and worker node cluster)
Eg :
manager --- 132.92.41.4
worker --- 132.92.41.5
You can create these nodes in any of public cloud providers like AWS EC2 instances or GCP VMs etc
Next, You need to do below set of steps
Configure Hosts
Install Docker-ce
Docker Swarm Initialization
You can refer this article for more info https://www.howtoforge.com/tutorial/ubuntu-docker-swarm-cluster/
This completes first part of your assignment.
Next, You can create one small shell script and include all those install and configuration commands in that script. Basically shell script is collection of set of linux commands. Instead of running each commands separately , you will run script alone and all set up will be done for you.
You can create small script using touch command
touch docker-swarm-install.sh
Specify proper privileges to script to make it executable
chmod +x docker-swarm-install.sh
Next include all your install + configure commands, which you have used earlier to do docker swarm set up in scripts (You can refer above shared link)
Now, when your script is ready, you can configure this script in jenkins job and whenever jenkins job is run, script will get execute and docker swarm cluster will be created
You need a jenkins server. Jenkins is open source software, you can install it in any of public cloud instance (Aws EC2)
Reference : https://devopsarticle.com/how-to-install-jenkins-on-aws-ec2-ubuntu-20-04/
Next once installation is completed. You need to configure job in jenkins
Reference : https://www.toolsqa.com/jenkins/jenkins-build-jobs/
Add your 'docker-swarm-install.sh' as build step in created job
Reference : https://faun.pub/jenkins-jobs-hands-on-for-the-different-use-cases-devops-b153efb483c7
If all set up is successful and now when you run your jenkins job, your docker swarm cluster must be get created.
I am using user-data of ec2 instance to power up my auto scale instances and run the application. I am running node js application.
But it is not working properly. I have debugged and checked the instance cloud monitor output. So it says
pm2 command not found
After reading and investigating a lot I have found that the path for the command as root is not there.
As EC2 user-data when it tries to run it finds the path
/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin
After ssh as ec2-user it is
/usr/local/bin:/usr/bin:/usr/local/sbin:/usr/sbin:/home/ec2-user/.local/bin:/home/ec2-user/bin
After ssh as sudo su it is
/root/.nvm/versions/node/v10.15.3/bin:/sbin:/bin:/usr/sbin:/usr/bin
It works only for the last path.
So what is the way or script to run the command as root during launch of the instance provided by user-data?
All thought to start your application with userdata is not recommended, because as per AWS documentation they are not assuring that instance will only come up after successful execution of user data. Even if user data failed it will spin up your instance.
For your problem, I assume if you give the complete absolute path of the binary, It will work.
/root/.nvm/versions/node/v10.15.3/bin/pm2
Better solution for this approach, create a service file for your application startup and start application with systemd or service.
I'm trying to get a amazon ec2 instance to automatically reboot each 2 hours, and after run a shell (.sh) script on startup. Any ideas?
For rebooting after 2 hours, if it is Ubuntu (or Debian based distro) just put on root's cron (by entering sudo crontab -e):
* */2 * * * /sbin/shutdown -r now
I am very curious as to why you need to reboot every 2 hours... I hope this is not a production server... but you could run a cronjob to do the rebooting, what type of instance do you have, is it linux or windows?
I have a centos instance and I have modified /etc/rc.d/rc.local to run a script after booting up but then again you could easily run a script via cronjob to check whether something is running or not...
I guess we need more information from you as to what you are trying to do and what type of instance you have.
need pretty trivial task
i have server, which in crontab every night will run "something" what will launch new EC2 instance, deploy there code (ruby script), run it, upon completion of the script shutdown the instance.
how to do it the best?
thanks.
Here's an approach that can accomplish this without any external computer/cron job:
EC2 AutoScaling supports schedules for running instances. You could use this to start an instance at a particular time each night.
The instance could be of an AMI that has a startup script that does the setup and running of the job. Or, you could specify a user-data script be passed to the instance that does this job for you.
The script could terminate the instance when it has completed running.
If you are running EBS boot instance, then shutdown -h now in your script will terminate the instance if you specify instance-initiated-shutdown-behavior of terminate.
i wanted to automate the ec2 instance's start & stop and configured the crontab on an instance x. I followed these steps
1) Edited the crontab -e of instance X.
2) and added these lines
15 04 * * * username ec2-start-instances i-f1814c90
15 07 * * * username ec2-stop-instances i-f1814c90
10 10 * * * username ec2-start-instances i-f1814c90
3) and restarted the cron using sudo /etc/init.d/cron restart
But still am unable to either start or stop the ec2 instance using cronjob.
thanks,
Anand
Most likely the issue is that the AWS data need to run the ec2 start and stop commands are not in the cron environment.
Its better to write a separate script that does this, instead of of making the ec2 commands on the cron like that.
This is why AWS Data Pipeline is for (working fine):
https://aws.amazon.com/premiumsupport/knowledge-center/stop-start-ec2-instances/
Just mind the trap: --region eu-west-1 NOT --region eu-west-1a (which is an availability zone).
I'd suggest to Schedule EC2 Start / Stop using AWS Lambda
You don't need anything more than a small script or two that you schedule. No instance to launch, just a quick invocation of the script you have built. Pick the programming language of your choice and use the AWS SDK to perform instance operations. A quite lightweight solution,.