rsync

Short Instructions

These instructions apply to ClickHouse using default locations for storage.

1. Do FREEZE TABLE on needed table, partition. It produces a consistent snapshot of table data.

2. Run rsync command.

   rsync -ravlW --bwlimit=100000 /var/lib/clickhouse/data/shadow/N/database/table
       root@remote_host:/var/lib/clickhouse/data/database/table/detached
   

   --bwlimit is transfer limit in KBytes per second.

3. Run ATTACH PARTITION for each partition from ./detached directory.

IMPORTANT NOTE: If you are using a mount point different from /var/lib/clickhouse/data, adjust the rsync command accordingly to point the correct location. For example, suppose you reconfigure the storage path as follows in /etc/clickhouse-server/config.d/config.xml.

<clickhouse>
    <!-- Path to data directory, with trailing slash. -->
    <path>/data1/clickhouse/</path>
    ...
</clickhouse>

You’ll need to use /data1/clickhouse instead of /var/lib/clickhouse in the rsync paths.