Overland Storage NEO 200S User Manual page 32

NEO 200s/400s User Guide
• LN Port: (default setting) – an automatic configuration that tries arbitrated loop first,
then switched fabric
• L Port – arbitrated loop
• N Port – point to point protocol in a switched fabric topology
Cables and Speeds
Ultrium 4 and Ultrium 5 Fibre Channel tape drives use LC duplex fiber optics cables.
The maximum distances that the library supports on a Fibre Channel link is determined by
the link speed, the type of fiber (50-micron or 62.5-micron), and the device to which the
library is attached.
If the library attaches to an HBA (Host Bus Adapter), refer to the distances that are
supported by the HBA. If the library attaches to a switch, the supported distances are:
• For a multi-mode 50-micron cable:
• 1-Gbit link speed = up to 500 m (1640 ft.)
• 2-Gbit link speed = up to 300 m (984 ft.)
• 4-Gbit link speed = up to 175 m (574 ft.)
• 8-Gbit link speed = up to 150 m (492 ft.)
• For a multi-mode 62.5-micron cable:
• 1-Gbit link speed = up to 300 m (984 ft.)
• 2-Gbit link speed = up to 90 m (295 ft.)
• 4-Gbit link speed = up to 50 m (164 ft.)
• 8-Gbit link speed = up to 21 m (68 ft.)
NOTE: Minimum distance for both 50 micron and 62.5 micron is 2 m (6 ft.).
Using Zoning to Isolate Devices and Enhance Security
For security reasons, it is important to limit the devices that a server or servers can
recognize or access. Also, some performance configurations and SAN configurations can
result in a device being seen multiple times from the same server. For example, if you have
two HBAs from the same server connected to an Ultrium Tape Drive in the library, the
drive will be detected and appear as two logical devices. That is, there will be two special
files for one physical device. Zoning can address these issues.
Zoning allows you to partition your SAN into logical groupings of devices so that each group
is isolated from the other and can only access the devices in its own group. Two types of
zoning exist: hardware zoning and software zoning. Hardware zoning is based on physical
fabric port number. Software zoning is defined with a World Wide Node Name (WWNN) or
World Wide Port Name (WWPN). While zoning can be reconfigured without causing an
outage, some zoning configurations can become complicated. The advantage of the library's
WWNN implementation is that you can avoid the exposure of introducing zoning errors
because you do not have to change the zoning configuration if a drive needs service or
replacement.
IMPORTANT: It is recommended that tape storage devices be connected on a separate HBA
from disk storage devices to avoid potential configuration incompatibilities.
10400367-001 04/2012
©2012 Overland Storage, Inc.
Host Interfaces
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