Quantum SNC 4500, User Manual

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50 Troubleshooting
Checking the Host System
The faster the host, the faster your transfer times will be. The work flow goes only as fast as the slowest
connection in the host system, so transferring data from an IDE drive, 100Mb connection, a DLT 4000, a
high speed RAID volume across the country, or other applications, slows the system no matter how fast
everything else is in the system.
1 Verify that the iSCSI storage adapter or NIC is connected to the fastest PCI bus connector supported
by the adapter or NIC.
If the adapter supports PCI-X, place the adapter in a PCI-X slot. If one is not available, the host might
not achieve the optimal performance capable from the adapter.
Even placing a PCI-X adapter into a 64 bit 66 MHz slot loses performance. Some adapters adjust clock
speed depending on the speed of the PCI slot into which they are plugged.
2 The host OS disk and swap disk/partition/file should be on a high speed drive such as a SCSI drive to
minimize the time needed to access the host’s virtual memory.
The more memory a system has, the less time it spends accessing virtual memory (hard drive space).
Checking the Operating System
If possible, eliminate swap space and virtual drives which require large amounts of system memory.
However, the OS might not allow the elimination of swap space. An OS set to run many kinds of different
servers spends much of its CPU cycles on other operations, thus slowing down performance.
Using Jumbo Frames
Verify that if you are using jumbo frames, your data path (all hardware between the host and target including
switches and routers) supports jumbo frames. Set the host and the SNC to 1.5K frames.
Updating Firmware
3 Verify that your FTP client is set for binary mode.
4 Try uploading the firmware through the serial port using the ZModem protocol. Refer to Updating
Firmware Using ZModem on page 34.
WARNING
DO NOT INTERRUPT THE UPDATE PROCESS. DO NOT TURN OFF
THE PERSONAL COMPUTER OR THE SNC UNTIL READY IS
RETURNED AT THE END OF THE UPDATE. INTERRUPTING THE
UPDATE PROCESS WILL MAKE YOUR SNC INOPERABLE AND YOU
WILL HAVE TO RETURN IT FOR REPAIR.