[CASSANDRA-7779] Add option to sstableloader to only stream to the local dc

• Type: Improvement
• Status: Open
• Priority: Normal
• Resolution: Unresolved
• Fix Version/s: 2.1.x
• Component/s: Legacy/Tools
• Assignee: Unassigned
• Reporter: Nick Bailey
• Created: 15/Aug/14 17:36
• Updated: 16/Apr/19 09:31

Description

This is meant to be a potential workaround for CASSANDRA-4756. Due to that ticket, trying to load a cluster wide snapshot via sstableloader will potentially stream an enormous amount of data. In a 3 datacenter cluster with rf=3 in each datacenter, 81 copies of the data would be streamed. Once we have per range sstables we can optimize sstableloader to merge data and only stream one copy, but until then we need a workaround. By only streaming to the local datacenter we can load the data locally in each datacenter and only have 9 copies of the data rather than 81.

This could potentially be achieved by the option to ignore certain nodes that already exists in sstableloader, but in the case of vnodes and topology changes in the cluster, this could require specifying every node in the cluster as 'ignored' on the command line which could be problematic. This is just a shortcut to avoid that.