Affects Version/s: None
Fix Version/s: None
The Solr core restore functionality uses following criteria to decide if a given file is copied from backup directory or from current index directory.
case 1] File is available in both backup and current index directory
--> Compare the checksum and file length
--> If checksum and length matching, copy the file from current working directory.
--> If the checksum and length doesn't match, copy the file from backup directory.
case 2] File is available in only in backup directory (This can happen for a newly created core without any data).
--> Copy the file from backup directory.
Now the problem here is that we intentionally catch and ignore the error while reading the checksum for a file in the backup directory. Hence in case (2), it will result into restoration of a file without appropriate "checksum".