Building clusters is usually a fun time. Here’s one of my setups at the Equinix LAX1 facility that is being used for VPN services, OpenVZ clustering, and general RADIUS and MySQL clustering integration. Once the clustering design is finalized, it’s still in flux state while I try out different setups, I’ll post some physical+logical architecture diagrams to show “How to Build a Fault Tolerant Infrastructure for Virtualized MySQL NDB Cluster + Python-based VPN systems.” Stay tuned for more.

Sometimes we encounter odd application responses that seem to make no sense. One of these such issues is related to running virtual server instances (OS Containers not Para-Virtualized VMs) and attempting to back up their data to Amazon’s S3 cloud storage. For moderately sized virtual machines running MySQL databases or Python/PHP based websites and code repositories this can be an inexpensive, quickly provisioned, and easy way to provide disaster recovery backups in numerous geographic locations, since we generally want DR content to be located in a physically distant location. Nevertheless, we can encounter errors if using an S3 mount in a distance location from our server if the timezone/sync data is incorrect.

The commonly seen error is as follows – and it doesn’t give much information for troubleshooting and resolution.

WARNING: Upload failed:  ([Errno 32] Broken pipe)
WARNING: Retrying on lower speed (throttle=0.00) …

I’ve released version 1.1.6 of the Better Cacti Templates project. This release includes a bunch of bug fixes (but not all of them!) and two new sets of graphs. One set is for disk I/O on GNU/Linux, and the other is a new set of templates for OpenVZ. I’m looking for feedback on both of those. This release also has a bunch of code-level features: much better test coverage (hooray!), and a refactored ss_get_by_ssh.php that makes it much easier to create new graphs and templates. The SSH-based templates also take advantage of the same caching as the MySQL templates, which makes them a lot more efficient.

There are upgrade instructions on the project wiki for this and all releases. There is also a comprehensive tutorial on …