ATTO Technology 1550D Benutzerhandbuch

20

7

Some older switches cannot autonegotiate 
between the host and the switch properly. You 
may have to force the host or switch to the 
desired speed.

For a NIC using an OS iSCSI driver, continue to 
the iSCSI OS driver section.

Check the iSCSI OS driver
This section is for hosts using a driver that allows 
the OS to talk to iSCSI targets via a NIC, not an 
iSCSI storage adapter.

1

A PC using an iSCSI storage adapter and an 
iSCSI OS driver might not work correctly on the 
same machine. Check with the vendors to 
make sure they are compatible. 

2

Verify that the PC has the latest iSCSI driver as 
well as the required service packs and patches. 
Check with the iSCSI OS driver vendor for more 
information.

3

Verify that the iSCSI OS driver has started. 
Look under Device Manager for Windows or 
lsmod for Linux.

4

Verify that the iSCSI OS is still looking for the 
iPBridge at the right IP address. 

5

If using DHCP, verify that the DHCP server is 
assigning the correct IP information to the host. 

6

Verify that the NIC is configured with the correct 
IP information.

7

Verify that the hosts and the iPBridge are using 
the same port number to communicate via 
iSCSI. The default port number for the iPBridge 
is 3260. 

8

Check cable integrity. Check the cables for 
solid connections. Make sure they are plugged 
in properly. Inspect cable ends for broken clips 
and improper wiring.

1

Verify that the OS has the required service 
packs or patches installed. If not, obtain the 
proper service packs and patches and install 
them.

2

Some iSCSI host adapters and iSCSI OS 
drivers do not always automatically find new 
targets when plugged in or when forced to 
rescan. Reboot the hosts. 

3

Check if the vendor has a new driver. If so, 
install it.

1

Verify that the application is running the latest 
device drivers for the devices connected to 
iPBridge. If not, get the latest device drivers and 
install them.

2

Verify with the application vendor if the iSCSI 
technology is supported on the version of the 
application being used.

If the host is not getting the performance it should, 
check the following items. 

1

Verify that the devices are running at their 
highest possible SCSI speed. 
Mixing SE and LVD devices on the same SCSI 
bus forces the speed of the bus to SE, thus 
slowing faster LVD devices. The iPBridge 
cannot accelerate an already slow device. 
Refer to 

 on page ii of the Appendix.

2

Verify that the proper terminator is being used. 
An SE terminator forces the SCSI bus to SE 
speeds.

1

Verify that the SCSI port configuration is set to 
the highest speed using the ExpressNAV 
interface, SCSI page.

The iPBridge SCSI port speed, wide 
negotiation, and sync negotiation settings all 
affect the speed of the port. By default, these 
settings are set for optimal speed.

1

Verify that the data port is set to auto negotiate 
or forced to 1000 Mb. 

2

Verify that the MTU size is set to optimal setting 
for the LAN/WAN environment. 
The current optimized frame size for the 
iPBridge is 9k. 

1

Verify that the MTU size is set to optimal setting 
for the LAN/WAN environment.
9k frame size is the current optimized frame 
size for the iPBridge. Many switch and router 
vendors do not support the larger frame size of 
9k or 16k.