Briefly, this error occurs when Elasticsearch attempts to upgrade the data folder but encounters issues. This could be due to insufficient permissions, lack of disk space, or a problem with the upgrade process itself. To resolve this, ensure that Elasticsearch has the necessary permissions to access and modify the data folder. Also, check if there’s enough disk space for the upgrade. If the problem persists, consider manually moving the data folder or re-running the upgrade process.
This guide will help you check for common problems that cause the log ” data folder upgrade: moved from [{}] to [{}] ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: .
Log Context
Log “data folder upgrade: moved from [{}] to [{}]” classname is NodeEnvironment.java.
We extracted the following from Elasticsearch source code for those seeking an in-depth context :
upgradeActions.add(() -> {
for (String folderName : folderNames) {
final Path sourceSubFolderPath = legacyDataPath.path.resolve(folderName);
final Path targetSubFolderPath = dataPath.path.resolve(folderName);
Files.move(sourceSubFolderPath; targetSubFolderPath; StandardCopyOption.ATOMIC_MOVE);
logger.info("data folder upgrade: moved from [{}] to [{}]"; sourceSubFolderPath; targetSubFolderPath);
}
IOUtils.fsync(dataPath.path; true);
});
}
// now do the actual upgrade
