Appendix D. Upgrade Instructions

Please follow these instructions when upgrading from Titan or an older JanusGraph release.

D.1. Upgrading from Titan

JanusGraph is based on the latest commit to the titan11 branch of Titan repo.

JanusGraph has made the following changes to Titan, so you will need to adjust your code and configuration accordingly:

  1. module names: titan-* are now janusgraph-*
  2. package names: com.thinkaurelius.titan are now org.janusgraph
  3. class names: Titan* are now JanusGraph* except in cases where this would duplicate a word, e.g., TitanGraph is simply JanusGraph rather than JanusGraphGraph

IMPORTANT If you are pointing JanusGraph at an existing Titan database you will need to set the ids.store-name property to titan_ids in your JanusGraph properties file. Failure to do this could result in id allocation issues. See 228 for more details.

The BerkeleyDB version has been updated, and it contains changes to the file format stored on disk. This file format change is forward compatible with previous versions of BerkeleyDB, so existing graph data stored with Titan can be read in. However, once the data has been read in with the newer version of BerkeleyDB, those files can no longer be read by the older version. Users are encouraged to backup the BerkeleyDB storage directory before attempting to use it with the JanusGraph release.