What is SAN Storage?

Storage Area Network (SAN) storage can be categorized into iSCSI storage and FC storage:
  • iSCSI storage is an SAN storage that uses the iSCSI protocol for data transmission. You can add an iSCSI SAN block as a Shared Block primary storage or pass through the block to a VM instance.
  • FC storage is an SAN storage that uses the FC technology for data transmission. You can add an FC SAN block as a Shared Block primary storage or pass through the block to a VM instance.

Scenarios

  • Passes through an iSCSI or FC disk to a VM instance.
  • Adds an iSCSI or FC disk as a shared block and takes the shared block as a Shared Block primary storage.

Considerations

iSCSI storage:
  • You can add a disk that is not attached to a VM instance as a Shared Block primary storage.
  • A logical unit number (LUN) that is added as a primary storage cannot be used for other purposes.
  • You can attach a disk that is not added as a primary storage to a VM instance.
  • You can attach a disk to multiple VM instances or attach multiple disks to one VM instance.
FC storage:
  • If a block device is not attached to a VM instance and the cluster where the block device resides is in normal state, you can add the block device as a Shared Block primary storage.
  • A logical unit number (LUN) that is added as a primary storage cannot be used for other purposes.
  • You can attach a block device that is not added as a primary storage to a VM instance.
  • You can attach a block device to multiple VM instances or attach multiple block devices to one VM instance.