Prior to remove a CN from a customer cluster, the customer is asked to erase the HDD(s) of the CN in order to keep his privacy of data. Although the HDD erasure could be managed by customer own methods, the MN provides various methods of HDD erasure, differing in number of deletion methods, cycles, and according runtime. A report is generated by the HDD erasure process and used for proof and audit purposes.
The HN requests from the PCM to reduce the number of CNs.
Along with the request to the PCM the HDD erasure report is presented. The PCM will not take back any nodes that have not been cleaned completely as residual data would possibly prevent the reuse of the node. The PCM “moves” the according CNs from the customer cluster to the pool cluster (=assigns them to the pool VLAN). The POOL nodes are cleaned again (2nd level HDD erasure, audit report) and provisioned with mini Linux on RAM disk prior to become indicated as reusable.