6.5.1

Table Of Contents
Procedure
1 In the vSphere Web Client object navigator, browse to a host, a cluster, a data center, or a folder that
contains hosts.
2 From the right-click menu, select Storage > Rescan Storage .
3 Specify extent of rescan.
Option Description
Scan for New Storage Devices Rescan all adapters to discover new storage devices. If new devices are
discovered, they appear in the device list.
Scan for New VMFS Volumes Rescan all storage devices to discover new datastores that have been added
since the last scan. Any new datastores appear in the datastore list.
Perform Adapter Rescan
When you make changes in your SAN configuration and these changes are isolated to storage accessed
through a specific adapter, perform rescan for only this adapter.
Procedure
1 Browse to the host in the vSphere Web Client navigator.
2 Click the Configure tab.
3 Under Storage, click Storage Adapters, and select the adapter to rescan from the list.
4 Click the Rescan Adapter icon.
Change the Number of Scanned Storage Devices
The range of scanned LUN IDs for an ESXi host can be from 0 to 16,383. ESXi ignores LUN IDs greater
than 16,383. The configurable Disk.MaxLUN parameter controls the range of scanned LUN ID range. The
parameter has a default value of 1024.
The Disk.MaxLUN parameter also determines how many LUNs the SCSI scan code attempts to discover
using individual INQUIRY commands if the SCSI target does not support direct discovery using
REPORT_LUNS.
You can modify the Disk.MaxLUN parameter depending on your needs. For example, if your environment
has a smaller number of storage devices with LUN IDs from 1 through 100, set the value to 101. As a
result, you can improve device discovery speed on targets that do not support REPORT_LUNS. Lowering
the value can shorten the rescan time and boot time. However, the time to rescan storage devices might
also depend on other factors, including the type of the storage system and the load on the storage
system.
In other cases, you might need to increase the value if your environment uses LUN IDs that are greater
than 1023.
vSphere Storage
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