Ask any MySQL Database Administrator or database-savvy Developer how smooth their last MySQL master/slave swap went, and unless they live in a perfect world, they likely encountered a hiccup or two.  The actual reconfiguration of replication probably went well, as “CHANGE MASTER TO” is hard to mess up if you’re being careful.   But controlling application behavior isn’t always easy, and can lead to attempted writes to the now-demoted master, which has likely just become a production slave.  For instance, applications that use DNS for database connectivity can cache the DNS entry that should normally point them to the correct MySQL master.  Sometimes, a configuration file is overlooked and the correct read/write host pairs are not updated correctly.  Often enough, a Database Administrator needs to perform an emergency master/slave swap and doesn’t have control over the behavior of the application(s) the database serves.  A clean architecture involving automation can help avoid these issues all-together, but in a typical environment, MySQL master/slave swaps are a common and manual process. (more…)

One of the hottest topics in computing today, by way of fast innovation and controversy, is whether or not to rely on the public cloud. Lured by the convenience and cost-effectiveness of these services, some computer users and business owners put their applications and data into the cloud without a moment’s hesitation.  For the most part, they entrust their data to complete strangers, using hardware they have no access to, from a base of operations they often don’t even know the location of.  Without an educated understanding of the cloud, they count on it without ever having to see it, just as children believe in Santa Clause. As long as the presents keep coming, who can blame them? (more…)

Over the past two years, I’ve had the opportunity to work with Rackspace Cloud on multiple levels and from multiple directions.  I’ve been quite impressed with the technology, the team’s knowledge and willingness to help customers, the advancement of features, and the growing community.

To be frank, some awesome things to mention about Rackspace Cloud: (more…)

We’re currently beginning a project that clones an environment currently setup at Amazon EC2 to Rackspace Cloud.  Both environments will operate mostly independently, but still need to be implemented in a similar fashion.  Without getting into too many details, I decided to make a quick blog post to compare the pros/cons of Amazon EC2 vs. Rackspace Cloud.  Rackspace Cloud has a great comparison page (from their perspective, of course).

Rackspace Cloud is a strong offering, and I can understand why it’s quickly becoming a market leader.  Their support is top-notch and offer an enterprise-level product.  Like Amazon EC2, they have an intuitive web interface, growing API, and competitive pricing.  Here are some things I’d like to see improved: (more…)

We’ve been working on a project using Amazon Web Services for the past few years.  One of the main concerns I have is the inability to change a server from one security group to another once deployed.  I’m sure there are very good reasons for security groups being designed this way (the setup is most likely iptables on the host node behind the scenes), but when trying to long-term EC2 instances, it’s a System Engineer’s worst nightmare to not have full control over firewall configuration.  Add in the fact that all general EC2 customers share a single private address space, and the need for flexibility becomes even more important. (more…)