Removing cold storage disks

Before physically disconnecting cold storage disks, remove these disks from the storage settings.

To remove a disk from the storage settings:

• In the KUMA web interface, under Resources → Storages, select the relevant storage.

  This opens the storage.

• In the window, in the Disks for cold storage section, in the required disk's group of settings, click Delete disk.

  Data from removed disk is automatically migrated to other cold storage disks or, if there are no such disks, to the ClickHouse cluster. During data migration, the storage status icon is highlighted in yellow. Audit events are generated when data transfer starts and ends.

• After event migration is complete, the disk is automatically removed from the storage settings. It can now be safely disconnected.

Removed disks can still contain events. If you want to delete them, you can manually delete the data partitions using the DROP PARTITION command.

If the cold storage disk specified in the storage settings has become unavailable (for example, out of order), this may lead to errors in the operation of the storage service. In this case, create a disk with the same path (for local disks) or the same address (for HDFS disks) and then delete it from the storage settings.