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Shelf Management
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R1.0, October 2018
9.9 Redundancy Control
The Shelf Manager supports redundant operation with automatic switchover
using redundant Shelf Managers. In a configuration where two Shelf Manager
are present, one acts as the active Shelf Manager and the other as a standby.
The Shelf Managers monitor each other and either can trigger a switchover if
necessary.
9.9.1 Hardware Redundancy Interface
The two Shelf Manager communicate over the TCP/IP based Software
Redundancy Interface (SRI) which is implemented via a pair of USB links
between the ShMM-700Rs. The active instance posts incremental state updates
to the backup via this interface. As a result, the backup can quickly step into the
active role if necessary.
The Hardware Redundancy Interface (HRI) between the two Shelf Manager
instances enables the exchange of hardware level ShMM-700R state
information, including the following:
•
Presence: each Shelf Manager instance knows whether the other instance
is present in the shelf.
•
Health: each instance knows whether the other instance considers itself
„healthy“.
•
Switchover: the backup instance can force a switchover if necessary.
The ACB-VI Hardware Redundancy Interface supports the upgrade from ACB-
V to ACB-VI in an ATCA System without interruption. For details see the
firmware release note.