Allocate channel for maintenance in RMAN

we use the allocate channel for maintenance command to perform maintenance tasks. Maintenance tasks are tasks such as delete, change or crosscheck operations. And we can not use maintenance channels within a run block.

Example:

RMAN> allocate channel for maintenance device type disk;
RMAN> delete backup of database completed before 'sysdate-3';

The allocate channel command allocates the previously unallocated disk channel to perform the deletion of the backups.