Managing the Physical Devices in a Virtual Storage Area Network

You can create a virtual SAN instance that represents all of or a subset of the physical devices that are reachable by an initiator port. By default, a virtual SAN instance represents the set of all physical devices that are reachable by the specified initiator port.

You can use the ldm add-vsan or ldm set-vsan command to specify the mask property, which controls how vSAN instances are created. You can create vSAN instances in the following ways:

  • mask=off . Create a vSAN instance that represents the set of all physical devices that are reachable by the specified initiator port. This method is used by default to create vSAN instances.

  • mask=on . Create a vSAN instance that represents a subset of the physical devices that are reachable by the specified initiator port.

When you use the ldm set-vsan command to specify the value of the mask property, the virtual SAN automatically notifies the virtual SCSI HBA instance that you changed the property value. If you change the mask property value to off, all devices that are reachable by the virtual SAN's initiator port become members of the virtual SAN. If you change the mask property value to on, the content of the virtual SAN's mask property value is reset to remove all physical device identification data. To populate the mask property with identification data, run the ldm add-vsan-dev command for each physical device you want to add to the virtual SAN.

Note:

When you issue the ldm set-vsan command, any running I/O commands are terminated gracefully. Subsequent I/O requests to a previously known vSAN member return an error stating that the device is no longer reachable.

When a virtual SAN instance has its mask property set to on, use the ldm add-vsan-dev command to add one or more physical devices with associated worldwide numbers (WWNs) to the virtual SAN instance. Use the ldm remove-vsan-dev command to remove a physical device with the specified WWN from the virtual SAN. Run the ldm remove-vsan-dev command for each physical device that you want to remove from the virtual SAN instance.

You can use the ldm list-vsan command to obtain information about a virtual SAN. The ldm list-vsan command lists the members of the specified virtual SAN. When mask=on, the output shows the WWN of each virtual SAN member. When mask=off, the output states that the mask property value is off.