Arda created SOLR-17460:
---------------------------
Summary: Error During Collection Migration from Solr 7.0 to Solr
8.4: Missing Files and Shard Restoration Failures
Key: SOLR-17460
URL: https://issues.apache.org/jira/browse/SOLR-17460
Project: Solr
Issue Type: Bug
Security Level: Public (Default Security Level. Issues are Public)
Components: hdfs, SolrCloud
Affects Versions: 8.4, 7.0
Reporter: Arda
I was attempting to migrate a collection with 3 shards from a Solr 7.0 cluster
to a Solr 8.4 cluster. The data is stored in HDFS. I followed the
backup-restore process but encountered issues with two of the shards during the
restoration.
h1. *Migration Process:*
*1-* *Backup Command:* To avoid timeouts, I initiated the backup with an async
parameter:
curl -k --negotiate -u :
'https://<solrNode>:<solrPort>/solr/admin/collections?action=BACKUP&name=<backupName>&collection=<solrCollectionName>x&location=<hdfsPath>&
async=12346'
*2- Copy Backup to Local:* After the backup, I copied the data from HDFS to the
local filesystem:
hdfs dfs --copyToLocal <backupPath> <localPath>
*3- Transfer Backup to New Cluster:* I then copied the backup files from the
older Solr node to the newer one:
scp -pr <localPath> <username>@<ip>:<localPathDestination>
*4- Prepare New HDFS Path:* On the new Solr cluster, I created a new directory
in HDFS and adjusted ownership:
hdfs dfs -mkdir <pathName2>
hdfs dfs -chown solr:solr <pathName2>
*5- Copy Backup to New HDFS Location:* I transferred the backup data from local
to the new HDFS path:
hdfs dfs --copyFromLocal <localPathDestination> <pathName2>
*6- Restore Collection:* Finally, I ran the restore command:
curl -k --negotiate -u :
'https://<solrNode>:<solrPort>/solr/admin/collections?action=RESTORE&name=<backupName>&collection=<solrCollectionName>x&location=<hdfs_path>&
async=12345'
h1.
*Issue:*
After the restore process completed, I found that two of the shards could not
be restored. The logs displayed the following errors:
*Error During Shard Restoration:*
ERROR [c: <solrCollectionName> s: shard2 r:core_node5 x: :
<solrCollectionName>_shard2_replica_n4] o.a.s.h.RequestHandlerBase
org.apache.solr.common. SolrException: Error CREATEing SolrCore
'<solrCollectionName>_shard2_replica_n4': Unable to create core
[:<solrCollectionName>_shard2_replica_n4] Caused by:
org.apache.solr.handler.component.QueryDocAuthorizationComponent.....
*FileNotFoundException and Index Corruption:*
WARN
(parallelCoreAdminExecutor-6-thread-7-processing-n:<solrNode>:<solrPort>_solrx:<solrCollectionName>_shard2
_replica_n1 <numbers> RESTORECORE) [x:<solrCollectionName>_shard2_replica_n1]
o.a.s.h. RestoreCore Could not switch to restored index. Rolling back to the
current index => org.apache.lucene.index.CorruptindexException: Unexpected file
read error while reading index.
(resource=BufferedChecksumIndexInput(segments_1g9dk))
Caused by: java.io. FileNotFoundException: File does not exist:
hdfs://<hdfsPath>/core_node2/data/restore/<fileName>
It appears that Solr is looking for a file in HDFS that doesn't exist, despite
no manual deletions being made. I cannot determine why these specific shards
failed to restore, or why the system is unable to locate the required files.
Expected Behavior:
The backup and restore process should complete without errors, and all shards
should be restored successfully to the new cluster.
Actual Behavior:
Two shards failed to restore, with errors related to missing files and index
corruption.
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
---------------------------------------------------------------------
To unsubscribe, e-mail: issues-unsubscr...@solr.apache.org
For additional commands, e-mail: issues-h...@solr.apache.org
