Migrate from Elasticsearch to Zilliz Cloud

This topic describes how Zilliz Cloud handles data type mapping, collection naming rules, and considerations when migrating from Elasticsearch.

For index settings and post-migration steps, see External Migration Basics.

Prerequisites

Before starting your Elasticsearch to Zilliz Cloud migration, ensure you meet these requirements:

Requirement	Details
Version compatibility	Elasticsearch 7.x or later
Network access	Source cluster must be accessible from the public internet
API access	Valid cluster endpoint or cloud ID with appropriate credentials
Vector field requirement	Each source index must contain at least one dense vector field

Requirement	Details
User role	Organization Owner or Project Admin
Cluster capacity	Sufficient storage and compute resources (use the CU calculator to estimate CU size)
Network access	Add Zilliz Cloud IPs to allowlists if using network restrictions

Understanding how Elasticsearch data types map to Zilliz Cloud is crucial for planning your migration:

Elasticsearch Field Type	Zilliz Cloud Field Type	Description
Primary key	Primary key	Automatically mapped. Enable Auto ID to generate new IDs (original values will be discarded).
dense_vector	FLOAT_VECTOR	Vector dimensions remain unchanged. Specify L2 or IP as the metric type.
text, string, keyword, ip, date, timestamp	VARCHAR	Set Max Length (1 to 65,535 bytes). Strings exceeding the limit can trigger migration errors.
long	INT64	-
integer	INT32	-
short	INT16	-
byte	INT8	-
double	DOUBLE	-
float	FLOAT	-
boolean	BOOL	-
object	JSON	-
arrays	ARRAY	-

Elasticsearch index names are transferred to Zilliz Cloud with the following considerations:

Scenario	Impact	Solution
Default naming	Collection names match source index names exactly	Names are preserved as-is from OpenSearch
Special characters	Index names with hyphens (-) or dots (.) will cause errors and prevent job submission	Manually rename indexes to use underscores or other valid characters
Naming conflicts	Cannot submit job if a collection with the same name already exists	Delete existing collection, choose a different database, or rename during migration configuration

The following features are not supported for Elasticsearch migration:

Limitation	Impact	Alternative
Dynamic to fixed field conversion	Cannot convert existing dynamic fields to fixed types	Fields maintain their original dynamic nature
Add more fields	Cannot add new fields during migration	Only existing Elasticsearch fields are migrated
Sparse vectors	Not supported in current release	Consider dense vector alternatives or contact support for roadmap