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DNA: SIP Registration Failures on Failover



SIP registrations transferring through a DNA on failover malfunction.


  • Datto Networking Appliance (DNA)


Network transitions are known to interfere with long lived connections like SIP sessions. Additionally, multiple layers of NAT, or an ALG at the LTE carrier or ISP-level (CG-NAT), may cause timeouts or unexpected loss of return-path connectivity to client devices with long lived sessions.

SIP ALG is not implemented on the DNA.


Configure your application to transmit SIP traffic on an alternate port. Common alternatives are 5061 or 5062.

Other recommended configurations that can be set on your application are:

  • Configure SIP Transport over TCP.
  • Setting the SIP Registration timer to be at least 600 seconds.
  • Toggling SIP Keepalive on.
  • Toggling SIP Outbound on.
  • Toggling NAT traversal either on, Auto, or ICE.

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