Hitachi Dynamic Link Manager Software Users Guide for Windows (7.6)

The Online Path Statuses
The online path statuses are as follows:
• Online
I/Os can be issued normally.
• Online(P)
A state in which a path in the Online status is in the waiting-to-execute
status to be taken offline.
This status occurs in a cluster configuration only.
The Online(P) status indicates that the user has requested an Online
path to be taken offline, for a path that is connected to an LU that is
currently performing reserve processing. I/O operations can still be issued
normally until the reserve processing on the LU finishes. After the reserve
processing finishes, the offline operation request will be performed and
the path status will become Offline(C).
The (P) means pending, which indicates that the operation to take the
path offline is in the waiting-to-execute status (i.e. a request has been
made).
• Online(E)
An error has occurred on the path, but none of the other paths that
access the same LU are in the Online status.
If none of the paths accessing a particular LU are in the Online status,
one of the paths is changed to the Online(E) status. This ensures that
the LU can be accessed through at least one path.
The (E) means error, which indicates that an error has occurred on the
path from some previous operation.
• Online(EP)
The status of an Offline(P) path changes to Online(EP) when the path
goes through the following process during reserve processing in a cluster
configuration:
a. When exactly two paths are connected to an LU and the user performs
an offline operation on the Offline(E) path to change it to
Offline(P) and the other path is Online(E).
b. When one path is Offline(P), the other path must be Online(E). If
HDLM detects an error in the Online(E) path, then the path statuses
will change as follows:
The Online(E) path changes to Offline(E).
The Offline(P) path changes to Online(EP).
If the reserve processing finishes after the path has changed from
Online(EP) to Offline(P), the offline operation will end successfully and
the path will change to Offline(C).
If the reserve processing finishes while the path is Online(EP), the offline
operation will fail and the path will change to Online(E).
•
Online(S)
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HDLM Functions
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Hitachi Dynamic Link Manager User Guide for Windows
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