After Scalr was set up as described in my first post, some additional configurations have to be done to get in detailed touch with Scalr 1.1.0.
First log in as admin user to the Scalr frontend and create a new system user (“Client”) and activate it. After successful login with the new created and active user, you have to enter your AWS credentials and upload your public and private key from your AWS account.

The next screenshot show the configuration within my user.

Be aware to set this configuration right otherwise you will not be able to proceed.

If all settings are correct, you will be redirected to your dashboard view (which is known from the admin view).

In the next step we create a so called “Farm”. Within this option we assigne “Roles” – that means we will instance images (you can take a look for the available images under the option “Roles”).

A Server Farm is a logical group of EC2 machines that serve your application. It can include load balancers, databases, web severs, and other custom servers. Servers in these farms can be redundant, self curing, and auto-scaling.

If you receive an error while loading the site – “Error Type: LoadXML Description: Incorrect XML”, you will get a solution here in this blog post by Octavian Neacsu. You have to modify your apache settings as mentioned in Octavian’s post.

When the farm is configured and set up, scalr build it when you click the save button (I decided to launch the instances manually). In the farm overview you can now launch the instances you need. For that you only have to click under “Farms” on “Roles -view”. Under the drop down “Options” button it is possible to launch instances manually.

If launching instances throws an exception as “… \nFatal error: Class \’HttpRequest\’ not found …” this post in Scalr discussion group will help you out of that problem.

When instances are launched successful it should look like this screenshot.

As the screenshot above shows, within my workflow, I launched 2 instances.

Details are available under “Intances>View”. In my case I launched for the start one base www and one app“Farm role”.

As best know from connecting to EC2 instances, you can download under “Farms” your private key and login via ssh with the command:

ssh -i <nameofyourfarm.pm> <public IP>

Don’t forget to chmod your private key, otherwise you will get an error like this: "It is recommended that your private key files are NOT accessible by others. This private key will be ignored."

At this point I want to warn you about a possible issue (I reported to the mailinglist): launched instances are not shown in the AWS console under “Instances”. You will only see them at the frontpage of the AWS console dashboard. But you can terminate the launched instances within the Sclar interface under “Instances » View” > “Options” > “Terminate” (you can enable the option “Decrease ‘Mininimum instances’ setting” – the detailed instances settings you can modify under “Edit Farm” > “Shared Roles” > “Scaling options”).

At this point Scalr is installed and configured with an another system user as the admin user. It is possible to add Farms and launch instances through EC2.

In the next step I will deploy a grails application in my Scalr environment and will do some loadbalancing and performance configurations and tests – Iwill post my results in my blog under the title “Scalr 1.1.0 – getting in touch – Part III”.

Feel free to comment …

The research project site is available here.

• On EC2, I am told that it may take ~5 minutes to start 32 nodes (depending on image size), so with high probability we will finish the LU benchmark within 100 + 300 = 400 secs.
• On the supercomputer, we can use Rich Wolksi’s QBETS queue time estimation service to get a bound on the queue time. When I tried this in June, QBETS told me that if I wanted 32 nodes for 20 seconds, the probability of me getting those nodes within 400 secs was only 34%–not good odds.

ianfoster.typepad.com, Ian Foster, Aug 2009

These comparisons depends from my point of view always on experienced data and mainly on your various scenario Neutral declarations are hard to find. I asked Thijs Metsch for some experienced data of RESERVOIR project he mentoined in Twitter. Looking forward for an answer from him…
Does anyone else have some own experienced data for starting EC2 images in different environments and with various scenarios?