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1. An SBC node experiences a hardware failure which triggers the functioning node to remain (or become) the primary SBC.
2. The SBC with the failed DSP20 module reboots, detects the DSP20 module failure during startup and returns to service with the DSP20 module disabled.
   1. Multiple reboot attempts may occur before the module is declared as failed.
   2. The module is disabled via hardware primitives (such as slot power-down or hold in reset) to ensure that a misbehaving board cannot interfere with system operation.
3. When establishing HA connectivity, the primary SBC discovers that the secondary has less DSP capacity.
4. The primary SBC automatically triggers a graceful dry-up in an attempt to align DSP hardware capabilities.
   1. During the dry-up period, active calls on the "extra" DSP module are not protected in the event that a switchover occurs before dry-up completes.
5. Once the dry-up completes, the primary SBC no longer uses the "extra" DSP module.
6. The pair is now redundant with reduced capacity.

1. An SBC node experiences a hardware failure, which triggers the functioning node to remain (or become) the primary.
2. The SBC with the failed DSP20 module reboots, detects the DSP20 module failure during startup and returns to service with the DSP20 module disabled.
   1. Multiple reboot attempts may occur before the module is declared as failed.
   2. The module is disabled via hardware primitives (such as slot power-down or pressing and holding in reset button) to ensure that a misbehaving module cannot interfere with system operation.
3. While establishing HA connectivity, the primary SBC discovers that the secondary SBC has less DSP capacity.
4. The primary SBC continues to use all DSP capacity as needed.

If a switchover occurs while operating in this mode, calls using DSPs on the primary SBC that correspond to the disabled slot on the secondary are not protected during switchover (that is, partial redundancy).