Cloud-Developer-Tips

The ElasticFox Firefox extension allows you to tag EC2 instances, EBS volumes, EBS snapshots, Elastic IPs, and AMIs. ElasticFox’s tags are stored locally within Firefox, so if you use ElasticFox from more than one browser your tags from one browser are not visible in any other browser. In this article I demonstrate how to copy tags from one ElasticFox installation to another. Where Are ElasticFox Tags Stored? My article about Tagging EC2 Instances Using Security Groups shows a brief walkthrough of using ElasticFox to tag instances. Under the hood, ElasticFox stores tags in the prefs.js file within your Firefox Profile directory. But instead of poking around in there directly, take a look at Firefox’s built-in interface to these preferences. It’s the about:config screen, and you get there by typing about:config into the address bar: ...

EBS offers the ability to have a “virtual disk drive” whose lifetime is independent of any EC2 instance. You can attach EBS drives to any running instance, and any changes made to the drive will persist even after the instance is terminated. You can also set up an EBS drive to be the root filesystem for an instance - giving you the benefits of an always-on instance but without paying for it when it’s not in use - and this article shows you how to do that. I also explore how to estimate the cost savings you can achieve using this solution. ...

Update March 2012: Amazon published their own official guide to ELB’s architecture and building and testing applications that use it. The official material is very consistent with the presentation offered here, more than two and a half years prior. Elastic Load Balancing is a long-anticipated AWS feature that aims to ease the deployment of highly-scalable web applications. Let’s take a look at how it achieves elasticity, based on experience and based on the information available in the AWS forums (mainly this thread). The goal is to understand how to design and test ELB deployments properly. ...

A common question about moving applications to EC2 is what to do about sending email. Web applications occasionally send email, to their administrators (“Help! I’m running out of disk space!”) or to their users (“Here is your forgotten password”), and this needs to work when the application is hosted within EC2 also. Unfortunately, it is not simple to send email reliably from within the cloud. Here are some tips about sending reliable email from EC2 instances. ...

So you purchased an EC2 Reserved Instance and you’re looking to see the reduced hourly rate take effect immediately. Don’t. Unlike all the other resources in EC2, which you can use immediately, reserved instances are not actually available until the credit card charge for your account is processed. You’ll need to wait until the next billing period begins the charge clears your credit card before the reserved instance is actually available and the discounted hourly rate takes effect. Until your credit card charge goes through, your instances will continue to be billed at the regular hourly rates. ...

Update September 2010: AWS has added support for tagging instances, volumes, snapshots, and many other EC2 resource types via the API and the AWS Management Console. The techniques described here are no longer necessary. So you have a bunch of instances running in Amazon EC2 and you want to be able to tell them apart easily. The way to do this is to “tag” each instance with a descriptive tag, such as “database”, “web server”, “memcached”, etc. The easy, human-friendly way to tag your instances is to use ElasticFox, and the robust, programming-friendly way is to use Security Groups. ...

Here you will find practical tips for developers who are using cloud computing. This is me on the Amazon Web Services EC2 support forum, where I’m a frequent poster answering questions and sharing practical advice based on my experience. My nickname there used to be “shl0m0”; you might see that reference in older posts. My experience includes more than 15 years of software development and software architecture. I’ve been building cloud-computing-based applications for clients (including my own company MyDrifts, where I am CTO and co-founder) since 2007.