[CASSANDRA-14412] Restore automatic snapshot of system keyspace during upgrade

• Type: Bug
• Status: Resolved
• Priority: Normal
• Resolution: Fixed
• Fix Version/s: 4.0-alpha1, 4.0
• Component/s: Local/Startup and Shutdown
• Severity: Normal
• Since Version: 4.0
• Assignee: Sam Tunnicliffe
• Reporter: Sam Tunnicliffe

Authors

Sam Tunnicliffe

Reviewers

Aleksey Yeschenko, Tommy Stendahl

• Created: 23/Apr/18 11:52
• Updated: 15/May/20 08:07
• Resolved: 17/Apr/19 14:35

Description

Since 2.2, the installed version is compared with the version persisted in system.local (if any) at startup. If these versions differ, the system keyspace is snapshotted before proceeding in order to enable a rollback if any other issue prevents startup from completing. Although the method to perform this check & snapshot is still present in SystemKeyspace, its only callsite was mistakenly removed from CassandraDaemon in CASSANDRA-12716.