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Failover SIP registration is for redundant SIP servers within a SIP Server Table (either multiple entries, or DNS SRV that returns multiple servers). If the SBC registration to the primary SIP Server fails, becomes unreachable, or the registrations expires and a re-register fails, the SBC attempts to register to the secondary SIP Server and continues calls to the server. Failover SIP registration is completed according to the Priority order of the SIP Servers. Fallback will occur if the primary SIP Server becomes reachable again.

Failover to another SIP server will also occur if the SBC receives the following SIP response code from an active SIP server: 4xx, 5xx, or 6xx.

Refer to Creating and Modifying Entries in SIP Server Tables for configuring Failover SIP Registration.

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