HP Hitachi Dynamic Link Manager Software - Manual (Page 55)

2. HDLM Functions
31
• All the paths connected to an LU are
Online(E)
,
Offline(E)
, or
Offline(C)
.
• All the paths connected to an LU have been determined to have an
intermittent error.
• The processing of continuous I/O operations issued to an LU is successful.
#2
When an Online or Offline(E) path exists among the paths that access the same
LU.
If there is only one available online path for an LU, it cannot be placed offline by
executing the
offline
operation. This ensures that the LU can always be accessed by
at least one path. For details on the
offline
operation, see 6.4 offline (Places Paths
Offline).
If an error occurs in the only available online path for an LU, the status of the path will
change to
Online(E)
.
If you are using the automatic failback function, after the path has recovered from the
error, HDLM will automatically place the path online.
When you are using intermittent error monitoring, the path in which the intermittent
error occurred is not automatically placed online when the path recovers from the error.
In such a case, place the path online manually.
Note:
If there is a path failure immediately after a path is taken offline by using either
the an HDLM command, the status might change from
Offline(C)
to
Offline(E)
. If an offline operation was just performed, wait about 1 minutes,
check the path status by using an HDLM command, and then make sure that the
status has changed to
Offline(C)
. If it is still
Offline(E)
, retry the offline
operation.