[SOLR-7887] Upgrade Solr to use log4j2 -- log4j 1 now officially end of life

• Type: Task
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 7.4
• Assignee: Erick Erickson
• Reporter: Shawn Heisey
• Created: 06/Aug/15 21:39
• Updated: 10/Apr/20 13:17
• Resolved: 05/Apr/18 18:10

Description

The logging services project has officially announced the EOL of log4j 1:

https://blogs.apache.org/foundation/entry/apache_logging_services_project_announces

In the official binary jetty deployment, we use use log4j 1.2 as our final logging destination, so the admin UI has a log watcher that actually uses log4j and java.util.logging classes. That will need to be extended to add log4j2. I think that might be the largest pain point to this upgrade.

There is some crossover between log4j2 and slf4j. Figuring out exactly which jars need to be in the lib/ext directory will take some research.

Issue Links

• blocks: SOLR-11453 Create separate logger for slow requests
• breaks: SOLR-12205 SOLR-7887 broke javadoc:jar in maven
• fixes: SOLR-11901 Improve how logging collects class name information
• is depended upon by: OFBIZ-6858 Solr logging doesn't work
• is depended upon by: SOLR-12055 Enable async logging by default
• is duplicated by: SOLR-8313 Migrate to new slf4j logging implementation (log4j 1.x is EOL)
• is duplicated by: SOLR-8684 Upgrade to LOG4J2
• is required by: SOLR-11453 Create separate logger for slow requests
• relates to: SOLR-11934 Visit Solr logging, it's too noisy.