Adaptec 5325301656 - Snap Server 14000 NAS, Administrator'S Manual

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iSCSI Configuration on the Snap Server
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the significant increase in write performance that write-cache provides, can disable
this feature for individual iSCSI disks.
Notes
• Write-cache can be disabled on an iSCSI-disk-by-iSCSI-disk basis. Disabling
write-cache for an iSCSI disk does not disable write-cache for any other iSCSI
disk or any other resources on the Snap Server.
• The opportunity to enable/disable write-cache for an iSCSI disk occurs only
when the disk is created; it cannot be toggled at a later date.
• Disabling write-cache for an iSCSI disk does not eliminate all potential risk of
data loss due to an unexpected loss of power as each disk drive contains its
own internal cache of 8 MB or more.
Disconnect iSCSI Disk Initiators before Shutting Down the Server
Shutting down the server while a client initiator is connected to an iSCSI disk
appears to the client initiator software as a disk failure and may result in data loss
or corruption. Make sure any initiators connected to iSCSI disks are disconnected
before shutting down the server.
Ignore the Volume is Full Message
When an iSCSI disk is created, the volume allocates the specified capacity to the
disk. If all volume capacity is allocated to the iSCSI disk and email notification is
enabled, the Snap Server may generate a Volume is Full message. This message
indicates only that the volume capacity is fully allocated to the iSCSI disk and is not
available to other resources. To determine the status of iSCSI disk storage
utilization, use the tools provided on the client machine.
iSCSI Disk Naming Conventions
iSCSI disks are assigned formal IQN names. These appear as the iSCSI device
names that the user chooses (or types) when connecting from a client initiator to the
Snap Server target, and also on the iSCSI Disk details page. The format of IQN
names for iSCSI disks on the Snap Server is:
iqn.1997-10.com.snapserver:[servername]:[diskname]
where [servername] is the name of the Snap Server, and [diskname] is the name of the
iSCSI disk on the target Snap Server. For example:
iqn.1997-10.com.snapserver:snap123456:iscsi0
Note
Users with iSCSI disks created in earlier GuardianOS versions will see a
shortened IQN name in the following format:
iqn.[servername].[iscsidiskname]