• Powered-off switches
• Failed host bus adapter ports
The first sign of a path failure, such as a disconnected Fibre Channel cable or a failed switch, is often an
alert or warning reported by the library in the web interface and event log. Failure of a single path to a
drive should not interfere with operation of most backup applications, and might go unnoticed. To ensure
that path failover functionality is restored for the next path failure, correct the problem as soon as
possible.
To locate and correct path failures:
Procedure
1.
Examine the library event or RAS ticket that indicates that a failover has occurred and locate the serial
number of the tape drive with the failed path.
The Serial # is that of the tape drive with the failed path and the tape drive coordinates indicate the
physical location of the drive. For information about tape drive location coordinates, see the library
user guide.
2.
Use host utilities to confirm the failure. On Windows, use the diagnostic application.
a.
Launch the application, or if it is already running, navigate to
Actions→Refresh Cached Driver
Data (F5)
.
b.
In the
Devices
pane, locate the drive whose serial number matches that from the support ticket.
Select the device.
c.
In the
Paths
pane, confirm that not all of the ports are available.
Commands for viewing tape and library devices connected to a system
3.
Locate the failed connection or SAN component.
a.
Using the location coordinates of the drive, locate the drive and examine the two Status LEDs
labeled “Port 1” and “Port 2.” If either of those LEDs is off, the port with the unlit LED is the failed
link.
b.
If the status LEDs are both lit and the library is connected to an external switch, use the Fibre
Channel switch management feature to locate ports that are not functioning.
c.
Examine the Fibre Channel host bus adapters in the host. If one has a light that indicates a
malfunction, that might be the problematic link.
4.
After correcting the connection problem, refresh the diagnostic application to confirm that all of the
expected failover paths are available on all devices. Launch the application, or if it is already running,
navigate to
Actions
>
Refresh Cached Driver Data (F5)
.
5.
In the
Devices
pane, locate the drive whose serial number matches that from the support ticket.
Select the device.
6.
In the
Paths
pane, confirm that not all of the ports are available.
Windows debugging logs and tools
Windows debugging logs and tools
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