move_chunk_experimental.md

api_name	move_chunk()
excerpt	Move a chunk to a different data node in a multi-node cluster
topics	distributed hypertables multi-node
keywords	multi-node chunks
tags	data nodes cluster rebalance rebalancing
api	license type experimental community function true

import MultiNodeDeprecation from "versionContent/_partials/_multi-node-deprecation.mdx";

import Experimental from 'versionContent/_partials/_experimental.mdx';

move_chunk() Community Experimental

TimescaleDB allows you to move chunks to other data nodes. Moving chunks is useful in order to rebalance a multi-node cluster or remove a data node from the cluster.

Required arguments

Name	Type	Description
chunk	REGCLASS	Name of chunk to be copied
source_node	NAME	Data node where the chunk currently resides
destination_node	NAME	Data node where the chunk is to be copied

Required settings

When moving a chunk, the destination data node needs a way to authenticate with the data node that holds the source chunk. It is currently recommended to use a password file on the data node.

The wal_level setting must also be set to logical or higher on data nodes from which chunks are moved. If you are copying or moving many chunks in parallel, you can increase max_wal_senders and max_replication_slots.

Failures

When a move operation fails, it sometimes creates objects and metadata on the destination data node. It can also hold a replication slot open on the source data node. To clean up these objects and metadata, use cleanup_copy_chunk_operation.

Sample usage

CALL timescaledb_experimental.move_chunk('_timescaledb_internal._dist_hyper_1_1_chunk', 'data_node_2', 'data_node_3');