[LUCENE-9127] index migration from 7 to 8 failing

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Information Provided
• Affects Version/s: 8.4
• Component/s: core/index
• Lucene Fields: New
• Assignee: Unassigned
• Reporter: Niranjan
• Created: 10/Jan/20 16:24
• Updated: 28/Aug/22 15:55
• Resolved: 10/Jan/20 17:19

Description

we have been using solr4 for more than 16 year, now it is to time to upgrade, when we have decided to upgrade, started with migrating index from 4 -> 5, 5 -> 6, 6 -> 7, it was working as expected, but when it comes to 7 -> 8 , it give me errors.

 Exception in thread "main" org.apache.lucene.index.IndexFormatTooOldException: Format version is not supported (resource BufferedChecksumIndexInput(MMapIndexInput(path="/deploy/solrmaster/data/data/<name>/index/segments_4n"))): This index was initially created with Lucene 6.x while the current version is 8.4.0 and Lucene only supports reading the current and previous major versions.. This version of Lucene only supports indexes created with release 7.0 and later.

java -cp ./lucene-core-8.4.0.jar:./lucene-backward-codecs-8.4.0.jar org.apache.lucene.index.IndexUpgrader /deploy/solrmaster/data/data/job/index -verbose