1.5 Upgrading From Previous Versions

Upgrading from 0.8.0, 0.8.1.X or 0.8.2.X to 0.8.3.0

0.8.3.0 has an inter-broker protocol change from previous versions. For a rolling upgrade:
  1. Update server.properties file on all brokers and add the following property: inter.broker.protocol.version=0.8.2.X
  2. Upgrade the brokers. This can be done a broker at a time by simply bringing it down, updating the code, and restarting it.
  3. Once the entire cluster is upgraded, bump the protocol version by editing inter.broker.protocol.version and setting it to 0.8.3.0.
  4. Restart the brokers one by one for the new protocol version to take effect
Note: If you are willing to accept downtime, you can simply take all the brokers down, update the code and start all of them. They will start with the new protocol by default. Note: Bumping the protocol version and restarting can be done any time after the brokers were upgraded. It does not have to be immediately after.

Upgrading from 0.8.1 to 0.8.2.0

0.8.2.0 is fully compatible with 0.8.1. The upgrade can be done one broker at a time by simply bringing it down, updating the code, and restarting it.

Upgrading from 0.8.0 to 0.8.1

0.8.1 is fully compatible with 0.8. The upgrade can be done one broker at a time by simply bringing it down, updating the code, and restarting it.

Upgrading from 0.7

0.8, the release in which added replication, was our first backwards-incompatible release: major changes were made to the API, ZooKeeper data structures, and protocol, and configuration. The upgrade from 0.7 to 0.8.x requires a special tool for migration. This migration can be done without downtime.