[CASSANDRA-15688] Invalid cdc_raw_directory prevents server startup

• Type: Bug
• Status: Resolved
• Priority: Normal
• Resolution: Fixed
• Fix Version/s: 4.0-beta1, 4.0
• Component/s: Feature/Change Data Capture
• Labels: pull-request-available
• Bug Category: Availability - Unavailable
• Severity: Normal
• Complexity: Low Hanging Fruit
• Discovered By: Adhoc Test
• Platform: All
• Since Version: 4.0

Source Control Link

https://github.com/apache/cassandra/commit/02c6d6540c6ab108b763a639146e74e9f8d0dd40

Test and Documentation Plan

Added tests for the factored out functionality. DatabaseDescriptor.applySimpeConfig is too monolithic to easily add a test to.

• Assignee: Jon Meredith
• Reporter: Jon Meredith

Authors

Jon Meredith

Reviewers

Dinesh Joshi

• Created: 02/Apr/20 21:49
• Updated: 15/Jul/21 20:01
• Resolved: 14/Apr/20 00:46

Description

If cdc_raw_directory is set to an invalid directory it prevents startup of the server even when cdc_enabled is set false.

The directory can either be set directly by the cdc_raw_directory setting in configuration YAML or indirectly via the cassandra.storage_dir system property, which is how I encountered it.

Easy to reproduce by setting cdc_raw_directory to notadir/notasubdir

Additionally while investigating, discovered that DatabaseDescriptor.guessFileStore can cause a NullPointerException if it runs out of parent elements
before it can get a FileStore. It should provide a more useful ConfigurationException providing details on the problematic path.
guessFileStore is used for checks on commitlog_directory, cdc_raw_directory and data_file_directories.

Issue Links

• supercedes: CASSANDRA-14570 Improper default value of cdc_total_space_in_mb
• links to: GitHub Pull Request #514