/jepsen

Call Me Maybe: simulating network partitions in DBs

Primary LanguageClojure

Jepsen

Breaking distributed systems so you don't have to. I'm tearing apart Jepsen as I work on the next iteration of the talk, so things are a bit messy. Pardon my dust.

If you came here looking for the tests from the first two jepsen talks, or for the foundationDB tests, you'll find them in the old branch. I've gutted the test rig for those systems and replaced it with something a lot faster and more powerful; if you want to help port the old tests forward, I could really use the help!

To get started, you'll need five debian boxes (I run debian testing, but some DBs don't need the latest packages so you might get away with an older distribution, or possibly ubuntu). I run em in LXC containers. Each one should be accessible via SSH. By default they're named n1, n2, n3, n4, and n5, but that (along with SSH username, password, identity files, etc) is all definable in your test. The account you use on those boxes needs sudo access to set up DBs and run firewalls. Be advised that it's gonna run killall -9 on some processes, so you shouldn't, you know, point jepsen at your prod machines. See lxc.md for some of my notes on setting up LXC instances.

Your local machine needs a JVM and leiningen installed.

For an overview of how a database test works, see elasticsearch/src/jepsen/system/elasticsearch.clj and its corresponding test elasticsearch/test/jepsen/system/elasticsearch-test.clj, which you can invoke via

lein with-profile +elasticsearch test jepsen.system.elasticsearch-test