Moving and restoring a ClickHouse® cluster

• What is the backup procedure for a ClickHouse® database?

• Is database host backup enabled by default?

• When are backups performed? Is a database cluster available during a backup?

• How many backups are stored in Managed Service for ClickHouse®? For how long?

• Can I delete a backup?

• Can I change the automatic backup retention period?

• What does a daily backup include?

• Why does it take a long time to restore a cluster from a backup?

• How do I move an existing ClickHouse® cluster to Yandex Cloud?

• Can I restore a shard from a backup into a shard in an existing cluster?

What is the backup procedure for a ClickHouse® database?What is the backup procedure for a ClickHouse® database?

Backups are created every 24 hours and stored for seven days after being created. You can restore data only as of the backup creation time.

Is database host backup enabled by default?Is database host backup enabled by default?

Yes, backup is enabled by default. For ClickHouse®, a full backup is performed once a day with the possibility to restore it to any saved backup.

When are backups performed? Is a database cluster available during backup?When are backups performed? Is a database cluster available during backup?

When creating or updating a cluster, you can set the time interval during which the backup will start. Default time: 22:00 - 23:00 UTC (Coordinated Universal Time).

Clusters remain fully accessible during the backup window.

How many backups are stored in Managed Service for ClickHouse®? For how long?How many backups are stored in Managed Service for ClickHouse®? For how long?

The size and amount of backups are not limited. Automatically created backups are stored for seven days, while manually created ones are stored indefinitely.

Can I delete a backup?Can I delete a backup?

Yes, if you created it manually. To delete a backup, follow this guide.

Can I change the automatic backup retention period?Can I change the automatic backup retention period?

You can set the retention period for automatic backups when creating or modifying a cluster.

What does a daily backup include?What does a daily backup include?

Backup data is only stored for the MergeTree engine family. For other engines, backups only store table schemas. For more information, see Backups.

Why does it take a long time to restore a cluster from a backup?Why does it take a long time to restore a cluster from a backup?

The approximate average speed of restoring a cluster from a backup is 100 Mbps. The recovery time may vary significantly depending on host class and the nature of data in the DB.

How do I move an existing ClickHouse® cluster to Yandex Cloud?How do I move an existing ClickHouse® cluster to Yandex Cloud?

Use Yandex Data Transfer.

Can I restore a shard from a backup into a shard in an existing cluster?Can I restore a shard from a backup into a shard in an existing cluster?

This option is not currently supported.

However, you can restore your shard from a backup to a new ClickHouse® cluster and transfer data from that cluster into an existing one. To do this, explore the below options:

• Data Transfer. You can use this service to transfer a database or separate tables to a Managed Service for ClickHouse® cluster.
• ClickHouse®'s built-in remote function. Use it to transfer separate tables to a Managed Service for ClickHouse® cluster.
• ClickHouse® BACKUP and RESTORE commands. These will help you to back up a database or single table to a Yandex Object Storage bucket and then restore your data from the bucket to a Managed Service for ClickHouse® cluster.

ClickHouse® is a registered trademark of ClickHouse, Inc.