I am using Jenkins v1.564 with the Amazon EC2 Plugin and set-up 2x AMIs. The first AMI has the label small and the second AMI has the label large. Both AMIs have the Usage setting set to Utilize this node as much as possible.
Now, I have created 2x jobs. The first job has Restrict where this project can be run set to small. The second job, similarly, set to large.
So then I trigger a build of the first job. No slaves were previously running, so the plugin fires up a small slave. I then trigger a build of the second job, and it waits endlessly for the slave with the message All nodes of label `large' are offline.
I would have expected the plugin to fire up a large node since no nodes of that label are running. Clearly I'm misunderstanding something. I have gone over the plugin documentation but clearly I'm not getting it.
Any feedback or pointers to documentation that explains this would be much appreciated.
Are the two machine configurations using the same image? If so, you're probably running into this: https://issues.jenkins-ci.org/browse/JENKINS-19845
The EC2 plugin counts the number of instances based on
Found there's an Instance Cap setting in Manage Jenkins -> Configure System under Advanced for the EC2 module, which limits how many instances can be launched by the plug-in at any one time. It was set to 2. Still odd as I only had one instance running and it wasn't starting another one (so maybe the limit is "less than" ). Anyway, increasing the cap to a higher number made the instance fire up.
Related
I was hoping to get some help/suggestions regarding my JMeter Master/slave test set up.
Here is my scenario:
I need to do load testing using Jmeter master slave set up. I am planning to launch the master and slave nodes on AWS (window boxes, dependency on one of the tool I launch via jmeter). I want to launch these master-slave set up in AWS on demand where I can tell how many slave nodes I want. I looked around a lot of blogs around using Jmeter with AWS and everywhere they assume these nodes will be launched manually and needs further configuration for master and slave nodes to talk to each other. For the tests where we might have 5 or 10 slave nodes this will be fine but for my tests I want to launch 50 instances(again the tool I use with jmeter has limitation that forces me to use each jmeter slave node as 1 user, instead of using 1 slave node to act as multiple users) like this and manually updating each of the slave nodes will be very cumbersome. So I was wondering if anybody else ran into this issue and have any suggestions. In the mean time I am looking into other solutions that will help me to use same slave node to mimic multiple users, which will help me to reduce the need to launch these many slave nodes.
Regards,
Vikas
Have you seen JMeter ec2 Script? It seems to be something you're looking for.
If for any reason you don't want to use particularly this script be aware that Amazon has the API to you should be able to automate instances creation by using a script AWS Java SDK or Amazon CLI.
You can even automate instances creation using a separate JMeter script with either JSR223 Sampler
or OS Process Sampler (this approach will require a separate JMeter script of course)
My company has thousands of server instances running application code - some instances run databases, others are serving web apps, still others run APIs or Hadoop jobs. All servers run Linux.
In this cloud, developers typically want to do one of two things to an instance:
Upgrade the version of the application running on that instance. Typically this involves a) tagging the code in the relevant subversion repository, b) building an RPM from that tag, and c) installing that RPM on the relevant application server. Note that this operation would touch four instances: the SVN server, the build host (where the build occurs), the YUM host (where the RPM is stored), and the instance running the application.
Today, a rollout of a new application version might be to 500 instances.
Run an arbitrary script on the instance. The script can be written in any language provided the interpreter exists on that instance. E.g. The UI developer wants to run his "check_memory.php" script which does x, y, z on the 10 UI instances and then restarts the webserver if some conditions are met.
What tools should I look at to help build this system? I've seen Celery and Resque and delayed_job, but they seem like they're built for moving through a lot of tasks. This system is under much less load - maybe on a big day a thousand hundred upgrade jobs might run, and a couple hundred executions of arbitrary scripts. Also, they don't support tasks written in any language.
How should the central "job processor" communicate with the instances? SSH, message queues (which one), something else?
Thank you for your help.
NOTE: this cloud is proprietary, so EC2 tools are not an option.
I can think of two approaches:
Set up password-less SSH on the servers, have a file that contains the list of all machines in the cluster, and run your scripts directly using SSH. For example: ssh user#foo.com "ls -la". This is the same approach used by Hadoop's cluster startup and shutdown scripts. If you want to assign tasks dynamically, you can pick nodes at random.
Use something like Torque or Sun Grid Engine to manage your cluster.
The package installation can be wrapped inside a script, so you just need to solve the second problem, and use that solution to solve the first one :)
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?
I am trying to understand how Amazon implements the auto scaling feature. I can understand how it is triggered but I don't know what exactly happens during the auto scaling. How does it expand. For instance,
If I set the triggering condition as cpu>90. Once the vm's cpu usage increases above 90:
Does it have a template image which will be copied to the new machine and started?
How long will it take to start servicing the new requests ?
Will the old vm have any downtime ?
I understand that it has the capability to provide load balancing between the VMs. But, I cannot find any links/paper which explains how Amazon auto scaling works. It will be great if you can provide me some information regarding the same. Thank you.
Essentially, in the set up you register an AMI, and a set of EC2 start parameters - a launch configuration (Instance size, userdata, security group, region, availability zone etc) You also set up scaling policies.
Your scaling trigger fires
Policies are examined to determine which launch configuration pplies
ec2 run instance is called with the registered AMI and the launch configuration parameters.
At this point, an instance is started which is a combination of the AMI and the launch configuration. It registers itself with an IP address into the AWS environment.
As part of the initial startup (done by ec2config or ec2run - going from memory here) - the newly starting instance can connect to instance meta data and run the script stored in "userdata". This script can bootstrap software installation, operating system configuration, settings, anything really that you can do with a script.
Once it's completed, you've got a newly created instance.
Now - if this process was kicked off by auto-scale and elastic-load-balancing, at the point that the instance is "Windows is ready" (Check ec2config.log), the load balancer will add the instance to itself. Once it's responding to requests, it will be marked healthy, and the ELB will start routing traffic.
The gold standard is to have a generic AMI, and use your bootstrap script to install all the packages / msi's / gems or whatever you need onto the server. But what often happens is that people build a golden image, and register that AMI for scaling.
The downside to the latter method is that every release requires a new AMI to be created, and the launch configurations to be updated.
Hope that gives you a bit more info.
may be this can help you
http://www.cardinalpath.com/autoscaling-your-website-with-amazon-web-services-part-2/
http://www.cardinalpath.com/autoscaling-your-website-with-amazon-web-services-part-1/
this post helped me achiving this
Have a read of this chaps blog, it helped me when I doing some research on the subject.
http://www.codebelay.com/blog/2009/08/02/how-to-load-balance-and-auto-scale-with-amazons-ec2/
Is there a way to have my hudson slaves used by multiple hudson masters?
A bit of background info:
My build guy has set-up separate hudson masters to do the deployment and testing of our solution into different test environments. My tests are run on hudson slaves (I have 4 slaves). These slaves are associated to one specific hudson master. I want the slaves to be available for use by any of the hudson masters.
I believe the build guy chooses to use multiple hudsom masters to manage the number of jobs on each master. His set-up for one environment has 8 view tabs therefore 5 environments would mean 40 tabs. Unfortunately as is common, the solution to one problem creates another.
Yes, you can add the slaves to both Hudson masters. The problem is that each master will not be aware of the resource utilization by the other master, so you'll have to figure out some mechanism for that, such as reducing the number of executors.
Even better would be to combine the two Hudson masters into a single Hudson instance. Your question doesn't explain the motivation for having two masters.
As I cannot comment above I'll try an answer.
I think you can have several independent slaves on same machine, each attaching and discussing with its unique master. I also think that different slaves on same machine sharing same home directory is not supported, not working. And of course if they are completely independent, as Michael Donohue said above, there is a workload sharing issue to resolve.
v1.366 added support for Windows slaves running as a Win32 service to serve multiple masters
see http://hudson-ci.org/changelog.html
Hudson jobs can also be parameterized, with a default value used for scheduled jobs and a web page offered for parameter input on manually triggered jobs. That can work in some situations to reduce need for multiple jobs.
Or try the nested view plugin if number of tabs an issue and can't reduce number of jobs