Source note · Setting up an Oracle SBC for Teams Direct Routing

When the SBC receives a 503 with a Retry-After header in response to an INVITE it must terminate that connection and try the next available Microsoft datacenter, and the SBC must not retry a call on a 603 response.

Checked 2026-09-30

Vendor: Microsoft
Product: Microsoft Teams Phone Direct Routing
Subsystem: SIP failover
Deployment: multi-tenant
Region: not restricted
Release range: current as of 2026-09-30
Checked: 2026-09-30

Sources

Teams Phone System Direct Routing: SIP protocol — Microsoft · tier 2 current vendor documentation · Retry-After; Handling retries (603 response)

Cite this note

APA

WarmTransfer. (2026, September 30). Setting up an Oracle SBC for Teams Direct Routing: source note oracle-sbc-teams-direct-routing-setup-503-603-handling. WarmTransfer. https://warmtransfer.net/knowledge/claims/oracle-sbc-teams-direct-routing-setup-503-603-handling

BibTeX

@misc{warmtransfer-claim-oracle-sbc-teams-direct-routing-setup-503-603-handling,
  title  = {Setting up an Oracle SBC for Teams Direct Routing: source note oracle-sbc-teams-direct-routing-setup-503-603-handling},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/oracle-sbc-teams-direct-routing-setup-503-603-handling},
  note   = {Source note oracle-sbc-teams-direct-routing-setup-503-603-handling, checked 2026-09-30}
}

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