Calls fail when VPN is on
VPN tunnel needs split-tunnel config, otherwise all RTP goes via VPN server.
Try this first
- 1Split tunnel: keep VoIP domain and SIP IP outside the tunnel
- 2Or route everything via tunnel with proper QoS on VPN server
- 3Lower MTU on VPN to 1400 if packets get fragmented
- 4Wireguard usually beats OpenVPN on latency
When to bring us in
Cannot split? Move cloud PBX SBC closer to the user.
See also
- Voys, BelXS or RoutIT, which cloud PBX fits?Three popular NL platforms, differences are admin UI, partner model and per-user price.
- Teams Phone: Calling Plan, Direct Routing or Operator Connect?Three ways to connect PSTN to Teams, cost and management differ a lot.
- 3CX: self-host on VPS or take 3CX cloud?Self-host saves licence, but you own SBC, backup and updates.
None of the above fits?
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