+h2(#main). development main (as of 2021-07-15)
+
+"Upgrading from 2.2.0":#v2_2_0
+
+h3. Storage classes must be defined explicitly
+
+If your configuration uses the StorageClasses attribute on any Keep volumes, you must add a new @StorageClasses@ section that lists all of your storage classes. Refer to the updated documentation about "configuring storage classes":{{site.baseurl}}/admin/storage-classes.html for details.
+
+h3. keep-balance requires access to PostgreSQL
+
+Make sure the keep-balance process can connect to your PostgreSQL server using the settings in your config file. (In previous versions, keep-balance accessed the database through controller instead of connecting to the database server directly.)
+
+h3. crunch-dispatch-local now requires config.yml
+
+The @crunch-dispatch-local@ dispatcher now reads the API host and token from the system wide @/etc/arvados/config.yml@ . It will fail to start that file is not found or not readable.
+
+h3. Multi-file docker image collections
+
+Typically a docker image collection contains a single @.tar@ file at the top level. Handling of atypical cases has changed. If a docker image collection contains files with extensions other than @.tar@, they will be ignored (previously they could cause errors). If a docker image collection contains multiple @.tar@ files, it will cause an error at runtime, "cannot choose from multiple tar files in image collection" (previously one of the @.tar@ files was selected). Subdirectories are ignored. The @arv keep docker@ command always creates a collection with a single @.tar@ file, and never uses subdirectories, so this change will not affect most users.
+
+h2(#v2_2_0). v2.2.0 (2021-06-03)