Administrator Guide

e) Click OK.
The Select Local User Groups dialog box closes.
7. Click OK.
The Edit Settings dialog box closes.
8. Click OK.
Delete a Directory User Group
Delete a directory user group if you no longer want to allow access to the directory users that belong to the group.
Steps
1. If you are connected to a Data Collector, select a Storage Center from the drop-down list in the left navigation pane of Unisphere
Central.
2. Click Summary.
The Summary view is displayed.
3. Click (Settings).
The Storage Center Settings dialog box opens.
4. Click the Users and User Groups tab.
5. On the Directory User Groups subtab, select the directory user group, then click Delete.
The Delete dialog box opens.
6. Click OK to confirm.
7. Click OK.
Managing Front-End I/O Ports
Front-end ports connect an Storage Center directly to a server using SAS connections or to the Ethernet networks and Fibre Channel
(FC) fabrics that contain servers that use storage. iSCSI, FC, or SAS I/O ports can be designated for use as front-end ports.
Front-End Connectivity Modes
Storage Center uses either legacy mode, virtual port mode, or ALUA port mode to transport data to servers that use SAN storage. In
legacy mode, front-end I/O ports are configured in pairs of primary and reserved ports. In virtual port mode, all ports are active, and if one
port fails the load is distributed between the remaining ports within the same fault domain. In ALUA port mode, volumes are mapped using
two paths, active and passive.
NOTE:
In Legacy mode, reserve ports and primary ports reside on separate controllers, providing controller-level
failover only. Legacy mode does not provide port-level failover.
The front-end connectivity mode is configured independently for Fibre Channel and iSCSI. Both transport types can be configured to use
the same mode or different modes to meet the needs of the network infrastructure. For example, a Storage Center can be configured to
use virtual port mode for iSCSI and legacy mode for FC.
• The front-end connectivity mode for FC and iSCSI ports is initially selected during Storage Center deployment.
• After deployment, the front-end FC and iSCSI ports can be changed from legacy mode to virtual port mode.
• After FC and iSCSI ports are configured for virtual port mode, they cannot be changed back to legacy mode.
NOTE:
Use legacy port mode only if the network environment does not meet the requirements for virtual port
mode.
• The front-end connectivity mode for SAS front-end is always ALUA port mode and cannot be changed.
Virtual Port Mode
Virtual port mode provides port and controller redundancy by connecting multiple active ports to each Fibre Channel or Ethernet switch.
In virtual port mode, each physical port has a WWN (World Wide Name), and is also assigned an additional virtual WWN. Servers target
only the virtual WWNs. During normal conditions, all ports process I/O. In the event of a port or controller failure, a virtual WWN will move
to another physical WWN in the same fault domain. When the failure is resolved and ports are rebalanced, the virtual port returns to the
preferred physical port.
Virtual port mode provides the following advantages over legacy mode:
• Increased performance: Because all ports are active, additional front-end bandwidth is available without sacrificing redundancy.
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Storage Center Maintenance