Today my friend and business partner Raphael pointed me to the new release of Scalr. I knew Scalr from the past, but i did not get in detailed touch yet. Scalr released version 1.1.0 under the GPL v2- and now I thought about to give it a detailed try.
Scalr promise alot of value within Cloud Computing and the use of Amazon EC2.
Scalr is a fully redundant, self-curing and self-scaling hosting environment using Amazon’s EC2.
It allows you to create server farms through a web-based interface using prebuilt AMI’s for load balancers (pound, nginx, or Amazon’s load balancing service), app servers (apache, rails, others), databases (mysql master-slave, others), and a generic AMI to build on top of.
The health of the farm is continuously monitored and maintained. When the Load Average on a type of node goes above a configurable threshold a new node is inserted into the farm to spread the load and the cluster is reconfigured. When a node crashes a new machine of that type is inserted into the farm to replace it.
Multiple AMI’s are provided for load balancers, mysql databases, application servers, and a generic base image to customize. Scalr allows you to further customize each image, bundle the image and use that for future nodes that are inserted into the farm. You can make changes to one machine and use that for a specific type of node. New machines of this type will be brought online to meet current levels and the old machines are terminated one by one.
Under http://www.scalr.net is also a pay service available, but i want to build my own environment.
If you want to install Scalr the wiki is a good starting point.
I droped some lines here in my blog to document my installation on a Ubuntu 9.04 Server.
Systemrequirements are definied on the project website as follows:
My server installation was build up with a LAMP. A good How-To for LAMP installation you can find here.
I had to customize my PHP5 installation for the required PHP extension listed in the project wiki. I searched for the plugins with following command
apt-cache search php5-*, and installed the required extensions manually.
Furthermore I created a database for scalr and a valid user for it.
# mysql -u -p
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 41
Server version: 5.0.75-0ubuntu10.2 (Ubuntu)
mysql> CREATE DATABASE ;
Query OK, 1 row affected (0.00 sec)
mysql> GRANT ALL PRIVILEGES ON .* TO ""@"localhost" IDENTIFIED BY "";
Query OK, 0 rows affected (0.00 sec)
mysql> FLUSH PRIVILEGES;
Query OK, 0 rows affected (0.01 sec)