Almanac
Microsoft/teamsMicrosoft 365

Consultant-focused KB for Microsoft Teams: implementation notes, gotchas and configuration decisions beyond the official docs — across chat and collaboration, meetings, webinars and town halls, Teams Phone, PSTN connectivity (Direct Routing, Operator Connect, Calling Plans, Teams Phone Mobile), auto attendants, call queues and contact centre integration, Teams Rooms and devices, apps and extensibility, Copilot in Teams, administration and governance, security and compliance, network and call quality, and licensing — plus cross-cutting decision guides.

teams/04-pstn-connectivity/feature-direct-routing-sbc-pairing.md/history
2 versions · feature-direct-routing-sbc-pairing.md
v2🤖 markdown-import3 weeks agomarkdown import
    … 36 unchanged lines …
  - Pairing success means nothing until OPTIONS flow both ways. `Enabled: True` on `Get-CsOnlinePSTNGateway` is config, not health — check the SBC health view in the admin center.
  - An IP in the Contact or Record-Route header is the classic half-working trunk: OPTIONS fail or calls 403.
  - Certificate renewal from a different CA, or an intermediate the SBC doesn't present, quietly kills TLS. Watch the root CA changes Microsoft announces — they've moved roots before and SBCs without the new trusted roots fail on mutual TLS.
+ - Moving an SBC off ACS Direct Routing (retiring 30 September 2028)? The same FQDN can't be paired with ACS and Teams at once. Either cut over and accept the propagation gap, or pair a second FQDN with a certificate covering both. ACS and Teams media ranges differ too, so redo the firewall rules. See [ACS retirement: what lands on Teams voice](https://365-almanac.app/kb/teams/feature-acs-retirement-teams-voice-impact).
  - Media bypass isn't supported on IPv6, and mixed IPv4/IPv6 on one gateway isn't supported.
  - AMR-WB is available only on non-bypass calls.
v1🤖 markdown-import3 weeks agomarkdown import
Initial version.