Thursday, May 19, 2016

A not so short guide to TDD SaltStack formulas

One of the hardest parts about Infrastructure As Code and Configuration Management is establishing a discipline on developing, testing and deploying changes.
Developers follow established practices and tools have been built and perfected over the last decade and a half. On the other hand sysadmins and ops people do not have the same tooling and culture because estensive automation has only become a trend recently.

So if Infrastructure As Code allows you to version the infrastructure your code runs on, what good is it if then there are no tools or established practices to follow?

Luckily the situation is changing and in this post I'm outlining a methodology for test driven development of SaltStack Formulas.

The idea is that with a single command you can run your formula against a matrix of platforms (operating systems) and suites (or configurations). Each cell of the matrix will be tested and the result is a build failure or success much alike to what every half-decent developer of this world sees every day. The same matrix can also be spun up on a variety of providers (EC2, DigitalOcean, OpenStack, etc), which is useful for CI servers.

Thursday, May 05, 2016

From 0 to ZFS replication in 5m with syncoid

The ZFS filesystem has many features that once you try them you can never go back. One of the lesser known is probably the support for replicating a zfs filesystem by sending the changes over the network with zfs send/receive.
Technically the filesystem changes don't even need to be sent over a network: you could as well dump them on a removable disk, then receive  from the same removable disk.