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they can be combined as a single filter entry (using either WWN as host WWN)
with Range Mask setting as 0xFFFFFFFF_FFFFFFFE. Note that under most
circumstances, the Range Mask is left as 0xFFFFFFFF_FFFFFFFF, which means
that only a single WWN is specified for that filter entry.
Filter Type
Each filter entry can be set to include or exclude certain host(s) from data access.
If a node's WWN falls in an ID range specified as Exclude, the related volume set
will be "invisible" to this node and no data access is possible.
If a node's WWN falls in an ID range specified as Include and does not fall in any ID
range specified as Exclude, this node will be allowed to access the data of the
related volume set.
The access mode can be specified as normal "Read/Write" or restricted "Read
Only".
If a node's WWN falls in none of the ranges and there is at least one Include-type
entry specified, this node is considered as Excluded; otherwise, it is considered
as Included.
Note that when no Filter Entries are specified for a volume set, any node can
access the volume set as there is no LUN masking.
Access mode
For certain applications, it is desired to limit the data access as "Read Only" such
that the data on the volume won't be accidentally modified. This can be done by
setting the Access Mode of the Included ID range as "Read Only". However, some
Operating Systems (e.g. Linux) may ignore this "Write Protect" attribute and still
issue write commands to the protected volumes.
"Data Protected" error will be response to these write commands then. It is sug-
gested to mount the volumes as "Read Only" for a consistent behavior, if possible.
Configuring
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