rqlite is an open-source distributed relational database, which uses SQLite as its storage engine. rqlite is written in Go and uses Raft to achieve consensus across a set of SQLite databases. It gracefully handles leader election, and can tolerate machine failure.
rqlite is a replicated relational database built on SQLite, with distributed consensus provided by the Raft consensus protocol. It gracefully handles leader election, and can tolerate machine failure.
rqlite provides robust replication for SQLite databases using the Raft consensus protocol. Coded in Go it ensures that all changes made to the leader SQLite database are replicated to all other nodes in the cluster, providing fault-tolerance and reliability.
It’s been 18 months since development of rqlite first started and it’s time for version 2.
I’ve started replacing go-raft within rqlite with the implementation from Hashicorp. go-raft is no longer maintained, and I’ve good experience with the Hashicorp code, due to my work with InfluxDB and hraftd. I’m also going to change the API, so it’s more useful. The existing implementation and API has been tagged as v1.0, so it’s still available.
You can follow the work on this branch, and I hope to merge it to master in the near future.
I recently presented at the InfluxDB San Francisco Meetup, on InfluxDB and the Raft consensus protocol. My talk was about the fundamental problems of distributed systems, and how InfluxDB uses Raft to solve these issues.
Hashicorp provide a nice implementation of the Raft consensus protocol, and it’s at the heart of InfluxDB (amongst other systems). I wanted to experiment with a simple system built using this particular Raft implementation, so was inspired by raftd to built hraftd.
SQLite is a “self-contained, serverless, zero-configuration, transactional SQL database engine”. However, it doesn’t come with replication built in, so if you want to store mission-critical data in it, you better back it up. The usual approach is to continually copy the SQLite file on every change.
I wanted SQLite, I wanted it distributed, and I really wanted a more elegant solution for replication. So rqlite was born.
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