– All affected servers are powered off.

Virtual disks are created and they are assigned as Virtual Adapter 1, Virtual Adapter 2, Virtual Adapter 3, or Virtual Adapter 4. For more information, see Applying Virtual Adapter Access Policy to Virtual Disks.

NOTE:

You can map only one virtual adapter to one server at a time.

Without an appropriate license, you can unmap a VA–server assignment, or map the VA to the default serve, only.

The default mapping is VA1–Server Slot 1, VA2–Server Slot 2, VA3–Server Slot 3, and VA4–Server Slot 4.

If full height server is inserted then the upper slot has the VA mapped to it while the bottom slot is still unmapped. For example a full height in slot 1 has VA1 assigned to slot 1 and VA3 is still unmapped.

If the system has an enterprise license then the you can assign any one of the four VAs to a server slot. However, you can still map one virtual adapter to one server at a time.

To map or unmap a virtual adapter from a server slot:

1.In the left pane, click Chassis Overview Storage Setup Virtualization. The Storage Virtualization page is displayed.

2.To select the required type of assignment, from the Assignment Mode: Virtual Disks to Virtual Adapters table, select:

Single Assignment — Select to assign one virtual disk to one virtual adapter.

Multiple Assignment — Select to assign a virtual disk to multiple virtual adapters. Read the on- screen instructions before selecting this option.

NOTE: Select the Multiple Assignment mode only when the servers have Cluster Services installed on them. Use of this mode without Cluster Services may lead to corrupted or lost data.

3.In the Virtual Adapters Mapped table, from the Action drop-down menu, select one of the following options, and then click Apply.

<Slot #> — Select the slot to which the VA must be assigned.

Unmap — Select to remove the VA assignment to a slot.

The VA is mapped or unmapped from the selected server slot, based on the selected action..

NOTE: Consider a VA assigned to server in the lower slot ( 3 or 4) . When a half height server (slot 3 or 4) is replaced with a full height server, the full height server does not access the VA assigned to lower slots. Inserting a half height server again, provides access to the VA.

Fault-Tolerance in Storage Controllers

High Availability (HA) in storage enables availability of multiple internal components and multiple access points to storage resources. In case a storage component stops functioning, the server is supported by a second critical component or path to the available data. High Availability only minimizes downtime by restoring services behind the scenes, in most cases before the non-functionality is visible, but does not eliminate downtime. Fault Tolerance (FT) makes use of redundant components within a storage system, which are configured to behave as backup components and are kept in standby mode. Storage Controllers in fault-tolerant mode prevent disruption of storage services and automatically take over the services of a component that has stopped functioning. Performance remains consistent throughout this

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Dell 2 manual Fault-Tolerance in Storage Controllers