---
title: "Troubleshoot"
url: "https://docs.yugabyte.com/stable/yugabyte-voyager/voyager-troubleshoot/"
---

# Troubleshoot

Troubleshoot issues in YugabyteDB Voyager.

Diagnose and troubleshoot issues when migrating to YugabyteDB using YugabyteDB Voyager

## Schema migration

### Invalid constraint type with PostgreSQL 17

When running the [assess migration](/stable/yugabyte-voyager/reference/assess-migration/#assess-migration "assess migration") or [export schema](/stable/yugabyte-voyager/reference/schema-migration/export-schema/ "export schema") commands on a PostgreSQL 17.0–17.2 source database, you may see the following error:

```output
pg_dump: error: query failed: ERROR:  invalid constraint type "n"
pg_dump: detail: Query was: EXECUTE getDomainConstraints('16452')
```

This error occurs when using pg\_dump version 17.6 with a PostgreSQL source database running versions 17.0, 17.1, or 17.2 that contains domain objects with NOT NULL constraints. A bug in PostgreSQL versions 17.0-17.2 causes `pg_get_constraintdef()` to not interpret NOT NULL domain constraints, leading to failure in pg\_dump version 17.6 when using this function to fetch schema information.

- Use an older version of pg\_dump.
  
  Use pg\_dump version 17.5 or earlier as follows:
  
  1. Install the pg\_dump version. The best practice is to use a pg\_dump version that matches your PostgreSQL server version (for example, use pg\_dump 17.2 with PostgreSQL 17.2).
  2. Ensure this version is the first pg\_dump executable in your system's PATH before you run Voyager.
- Upgrade PostgreSQL.
  
  Upgrade your PostgreSQL source database to version 17.3 or later, as the bug has been fixed in these releases.