[Freeswitch-users] No T38 SDP in 200 OK after glare

[Douglas Davenport]

After T38 reinvite glare on an inbound call, the provider resends their
reinvite after a random delay  (they own the call-ID). Freeswitch correctly
responds with 200 OK because fax_enable_t38=true however it does not
include SDP.  Are there any settings that would affect this behavior or is
this a bug? I'm aware that bug reports go to JIRA but I'm asking first to
know if this is actually a bug or I'm doing something wrong. Here is the
call flow. Note the starred 200 OK with no SDP:


                                Provider
 Freeswitch
      ──────────┬─────────          ──────────┬─────────
  12:07:02.067864   │ ─────── INVITE (SDP) ─────> │
  12:07:02.068654   │ <─────── 100 Trying ─────── │
  12:07:03.304619   │ <────── 200 OK (SDP) ────── │
  12:07:03.305554   │ ──────────── ACK ─────────> │
  12:07:06.506575   │ ────── INVITE (T38 SDP)───> │
  12:07:06.718790   │ <────── INVITE (T38 SDP)─── │
  12:07:06.719063   │ ───── 491 Request Pendi ──> │
  12:07:06.879340   │ <─────── 100 Trying ─────── │
  12:07:06.881990   │ <─────────── ACK ────────── │
  12:07:06.943138   │ <──── 491 Request Pendi ─── │
  12:07:06.943356   │ ──────────── ACK ─────────> │
  12:07:07.133006   │ <────INVITE (T38 SDP) ───── │
  12:07:07.133313   │ ──────── 100 Trying ──────> │
  12:07:07.146828   │ ─*************─ 200 OK ─[*NO SDP*]─> │
*****************
  12:07:07.280018   │ <─────────── ACK ────────── │
  12:07:16.012689   │ <─────────── BYE ────────── │
  12:07:16.026995   │ ────────── 200 OK ────────> │
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