---
title: "Database Migration Service troubleshooting"
slug: "dms-troubleshoot"
updated: 2026-10-08T06:43:42Z
published: 2026-10-08T06:43:46Z
canonical: "guide.ncloud-docs.com/dms-troubleshoot"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://guide.ncloud-docs.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Database Migration Service troubleshooting

Available in VPC

Learn how to resolve issues with Database Migration Service. Click any error for detailed troubleshooting steps.

## Troubleshoot common issues

The following are examples of common errors you might encounter:

[Migration error](/docs/en/dms-troubleshot-common#%EB%A7%88%EC%9D%B4%EA%B7%B8%EB%A0%88%EC%9D%B4%EC%85%98%EC%98%A4%EB%A5%98) Migration was not performed.

[Migration incomplete](/docs/en/dms-troubleshot-common#%EB%A7%88%EC%9D%B4%EA%B7%B8%EB%A0%88%EC%9D%B4%EC%85%98%EB%AF%B8%EC%99%84%EB%A3%8C) All migration steps, including replication, have been completed, but the status is displayed as "migration" in the Cloud DB for MySQL console.

[Migration error on definer account set in source DB](/docs/en/dms-troubleshot-common#SourceDB%EC%97%90%EC%84%A4%EC%A0%95%EB%90%9CDefiner%EA%B3%84%EC%A0%95%EB%A7%88%EC%9D%B4%EA%B7%B8%EB%A0%88%EC%9D%B4%EC%85%98%EC%98%A4%EB%A5%98) The definer account that is set in the source DB was not automatically created during migration.

[DB Config settings not migrated](/docs/en/dms-troubleshot-common#DBConfig%EC%84%A4%EC%A0%95%EC%9D%B4%EB%A7%88%EC%9D%B4%EA%B7%B8%EB%A0%88%EC%9D%B4%EC%85%98%EB%90%98%EC%A7%80%EC%95%8A%EC%9D%8C) DB Config settings were not migrated.

[Test Connection delay](/docs/en/dms-troubleshot-common#TestConnection%EC%A7%80%EC%97%B0) Test connection takes too much time.

["Killed $RESTORECMD$RESTORECMD" error popup appears when using mydumper.

[Permission error](/docs/en/dms-troubleshot-common#%EA%B6%8C%ED%95%9C%EC%98%A4%EB%A5%98) An insufficient privileges message is displayed.

## DB access setting problem

The following are examples of DB access errors you might encounter:

[Source DB and Target DB server communication error](/docs/en/dms-troubleshot-access#SourceDB%EC%99%80TargetDB%EC%84%9C%EB%B2%84%ED%86%B5%EC%8B%A0%EC%98%A4%EB%A5%98) Source DB and Target DB servers are not communicating.

[Source DB access error](/docs/en/dms-troubleshot-access#SourceDB%EC%A0%91%EC%86%8D%EC%98%A4%EB%A5%98) Attempted Test Connection but cannot access Source DB.

[Display DB ACL check message](/docs/en/dms-troubleshot-access#DBACL%EC%A0%90%EA%B2%80%EB%A9%94%EC%8B%9C%EC%A7%80%EB%85%B8%EC%B6%9C) When trying Test Connection, DB ACL check message displays.

[BACKUP_ADMIN/RELOAD permission](/docs/en/dms-troubleshot-access#BACKUPADMINRELOAD%EA%B6%8C%ED%95%9C) I want to use mydumper method, but I recieved the message BACKUP_ADMIN/RELOAD permissions.

## Migration between DBs of different versions

The following are examples of migration errors you might encounter:

[Compatibility issue](/docs/en/dms-troubleshot-version#%ED%98%B8%ED%99%98%EC%84%B1%EB%AC%B8%EC%A0%9C) When migrating from the lower version of MySQL to the higher version, a compatibility issue occurs.

[Error when migrating from Source DB MySQL version 5.7 and MariaDB version 10.1 or later to Target DB MySQL version 8.0](/docs/en/dms-troubleshot-version#SourceDBMySQL57%EB%B2%84%EC%A0%84%EB%B0%8FMariaDB101%EC%9D%B4%EC%83%81%EB%B2%84%EC%A0%84%EC%97%90%EC%84%9CTargetDBMySQL80%EB%B2%84%EC%A0%84%EC%9C%BC%EB%A1%9C%EB%A7%88%EC%9D%B4%EA%B7%B8%EB%A0%88%EC%9D%B4%EC%85%98%EC%8B%9C%EC%98%A4%EB%A5%98) Error occurs when migrating from Source DB MySQL version 5.7 and MariaDB version 10.1 or later to Target DB MySQL version 8.0.

[Replication consistency issues with MySQL 5.7.40](/docs/en/dms-troubleshot-version#MySQL5740%EB%B2%84%EC%A0%84%EC%97%90%EC%84%9C%EB%B0%9C%EC%83%9D%ED%95%98%EB%8A%94%EB%B3%B5%EC%A0%9C%EC%A0%95%ED%95%A9%EC%84%B1%EB%AC%B8%EC%A0%9C) Replication consistency issues occur in MySQL version 5.7.40.

["Collations unsupported in Target DB are included." Troubleshoot error messages](/docs/en/dms-troubleshot-version#TargetDB%EC%97%90%EC%84%9C%EB%8A%94%EC%A7%80%EC%9B%90%ED%95%98%EC%A7%80%EC%95%8A%EB%8A%94Collation%EC%9D%B4%ED%8F%AC%ED%95%A8%EB%90%98%EC%96%B4%EC%9E%88%EC%8A%B5%EB%8B%88%EB%8B%A4%EC%98%A4%EB%A5%98%EB%A9%94%EC%8B%9C%EC%A7%80) "Collations unsupported in Target DB are included." The error message appears.

## Learning resources

We offer various materials for you to explore. To learn more about Database Migration Service, check out these helpful links:

- FAQs: [Get answers to common Database Migration Service questions](https://www.ncloud.com/support/faq/prod?categoryCode2=DB&categoryCode3=SV_0219&page=1)
- \NAVER Cloud Platform blog: [Easily migrate DB to Cloud with Database Migration Service!

](https://blog.naver.com/n_cloudplatform/222934126770?trackingCode=blog_bloghome_searchlist){target="_blank"}

Note

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