HP Storage Mirroring V5 Software - Manual (Page 66)

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Auto-Disconnect and Auto-Reconnect
While disk queues are user configurable and can be extensive, they are limited by the amount of physical disk space available.
If the amount of disk space specified for disk queuing is met, additional data could not be added to the queue and data would
be lost. To avoid any data loss, the auto-disconnect and auto-reconnect processes occur.
Source —If disk queuing is exhausted on the source, Storage Mirroring will automatically start disconnecting connections. This
is called auto-disconnect. The transaction logs and system memory are flushed allowing Storage Mirroring to begin processing
anew. The auto-reconnect process ensures that any connections that were auto-disconnected are automatically reconnected.
Then, if configured, Storage Mirroring will automatically remirror the data. This process is called auto-remirror. The remirror
re-establishes the target baseline to ensure data integrity, so disabling auto-remirror is not advised.
Target —If disk queuing is exhausted on the target, the target instructs the source to pause. The source will automatically
stop transmitting data to the target and will queue the data changes. When the target recovers, it will automatically tell the
source to resume sending data. If the target does not recover by the time the source queues are exhausted, the source will
auto-disconnect as described above. The transaction logs and system memory from both the source and target will be flushed
then Storage Mirroring will auto-reconnect. If configured, Storage Mirroring will auto-remirror. The remirror re-establishes
the target baseline to ensure data integrity, so disabling auto-remirror is not advised.
NOTE: If there are errors during disk queuing on either the source or target, for example, Storage Mirroring cannot
read from or write to the transaction log file, the data integrity cannot be guaranteed. To prevent any loss of
data, the source will auto-disconnect and auto-reconnect. If configured, Storage Mirroring will auto-remirror.
The remirror re-establishes the target baseline to ensure data integrity, so disabling auto-remirror is not
advised.