Write Signature

You can use this feature on the signature cluster mode. When a disk has not been converted to signature mode, you can write the signature to the disk manually. You can do this through the disk details page or in batch mode through the cluster details page.

Note Use this command for converting a non-signature disk cluster to a signature disk cluster.

Caution When an enable or a disable encryption operation is performed on a disk, you must execute the copy running-config startup-config command on all the switches. Failure to do so results in Persistent Storage Service (PSS) on the switch which is inconsistent with the state of the disk as recorded in the CKMC.

Caution When an enable operation is performed on a signature mode cluster for the first time, ensure that there is sufficient LUN size for a 64 MB SME disk reserved space at the end of the disk. Failure to do so can result in data loss.

Note For signature mode clusters, enabling encryption is possible only if there is at least one I/O capable path available to the disk.

Note For asymmetric devices, an I/O capable path implies an Active Optimized (AO) path.

Note For signature mode clusters, there must be at least one I/O-capable path for recovery to succeed. As part of the recovery, SME disk clears the signature from the signature portion of the disk.

Note For signature mode clusters, there must be atleast one I/O- capable path for recover to succeed. As part of the recovery, SME disk writes the signature to the signature portion of the disk.

Recovering SME Disk from KMC

Note This is applicable only for signature mode clusters.

To recover SME Disk from KMC, SME Disk looks for an active key in KMC. After the active key is found, the active key is used to generate the signature written on the disk as the disk recovers to a crypto state.

Note The encryption key is the active key recorded in KMC.

Note If the KMC does not have an active key for the disk, then the disk recovers to a clear state and the signature in the reserved area is cleared.

Recovering SME Disk from Signature on Disk

Note This option is available only for signature mode clusters.

SME Disk gets the signature from the reserved area of the disk. If the signature is valid, SME Disk searches in the KMC using the GUID from the signature. If the KMC search succeeds, the disk recovers to a crypto state.

Note When the KMC search fails, the recover operation fails and the disk remains in failed state.

Note When there are no signatures found on the disk, the disk recovers to a clear state.