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Chapter 5: SAN LUN Mapping
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Overview
When attaching multiple host systems in a SAN environment, it may be necessary
to more precisely control which hosts have access to which logical drives. In addition
to controlling logical drive availability on a RAID controller on a port-by-port basis,
it is also possible to further restrict access to a specific logical drive. Up to 512 SAN
LUN mappings are supported.
Terminology
The following table describes the terminology relating to SAN LUN Mapping.
Term Description
Node Name This is an eight-byte hexadecimal number, uniquely identifying
a single host system. It incorporates the World Wide Name
and two additional bytes which are used to specify the format.
Port Name This is an eight-byte hexadecimal number, uniquely identifying
a single host port. It incorporates the World Wide Name and
two additional bytes which are used to specify the format and
indicate the port number.
Mapping Name A 32-character name that can be used to help identify the host
system.
Exclusive Access A logical drive is presented to only one host system. It is not
available to any other host systems.
Read/Write Access A logical drive will allow both reads and write operations.
Read Only Access A logical drive will not allow writes.
Mapped LUN
Number
This is the LUN number that a specific logical drive responds
to when accessed by a host. It is not necessary for this to bear
any relation to the LUN number.
Mapping Availability Which controller ports the mapping is valid for.