[SOLR-16475] Ability to change the default replica placement plugin though sysProp

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 9.2
• Assignee: Jan Høydahl
• Reporter: Jan Høydahl
• Created: 19/Oct/22 12:15
• Updated: 10/May/23 08:09
• Resolved: 06/Jan/23 01:21

Description

The default placement plugin is "Simple", and to change it you need to edit clusterprops.json in zookeeper, as specified in https://solr.apache.org/guide/solr/latest/configuration-guide/replica-placement-plugins.html.

The proposal is to be able to statically specify the default placement plugin to use as a system property or env.var, e.g.

solr start -c -Dsolr.defaultPlacementPlugin=affinity 

or

SOLR_PLACEMENTPLUGIN_DEFAULT=affinity solr start -c 

This will only change the default plugin to use instead of 'simple'. If users configure another plugin in clusterprops.json then things will work as today, that the explicitly configured plugin is used instead of the default.

This makes it easy to spin up Solr in Docker or with the solr-operator, using a different placement plugin default.

Issue Links

• relates to: SOLR-16492 Switch replica placement plugin default from 'simple' to 'affinity'
• links to: GitHub Pull Request #1089