Inbound calls failing in strange way

Clifford McGlamry · ‎03-25-2024

Customer has a gateway running MGCP. Gateway has an FXO card in it.

One of the ports has started acting strangely. Inbound callers to the number just hear ringing. The phone will ring 3 times and then simply stop. No forwarding set up on the phone. And it is set to ring for 120 seconds. The last 3 lines give me pause. I see "cc AllocateIF failed rc -6" and "mgcp_xlate_ccapi_error_cod(1115) and "error_tab_index = 16, protocol version 4"

I can't find a decoder ring for any of the above. The full string is below. Any suggestions? I've checked the obvious stuff and restarted the router. No change in behavior. This was previously working.

Debuging on the gateway, I ran across this:dpt NULL
Mar 25 2024 12:29:04.457 CDT: //-1/xxxxxxxxxxxx/MGCP/xgcp_endpt_get_by_ifn(1330):[lvl=0]Entered
Mar 25 2024 12:29:04.457 CDT: //-1/xxxxxxxxxxxx/MGCP/xgcp_endpt_get_tree_link_by_ifn(1149):[lvl=0]Entered
Mar 25 2024 12:29:04.457 CDT: //-1/xxxxxxxxxxxx/MGCP/xgcp_endpt_compute_key(198):[lvl=0]type 2 slot 0000 subunit 0001
Mar 25 2024 12:29:04.457 CDT: //-1/xxxxxxxxxxxx/MGCP/xgcp_endpt_get_state(3793):[lvl=0]endpt aaln/S0/SU1/0
Mar 25 2024 12:29:04.457 CDT: //-1/xxxxxxxxxxxx/MGCP/xgcp_endpt_default_get_state(3818):[lvl=0]endpt aaln/S0/SU1/0
Mar 25 2024 12:29:04.457 CDT: //-1/xxxxxxxxxxxx/MGCP/mgcp_endpt_get_notified_entity(452):[lvl=0]Entered
Mar 25 2024 12:29:04.457 CDT: //-1/xxxxxxxxxxxx/MGCP/mgcp_endpt_get_notified_entity(467):[lvl=1]ne 10.15.9.10:2427
Mar 25 2024 12:29:04.457 CDT: //-1/xxxxxxxxxxxx/MGCP/xlate_mgcp_ev(963):[lvl=1]hdr_type 1
Mar 25 2024 12:29:04.457 CDT: //-1/xxxxxxxxxxxx/MGCP|aaln/S0/SU1/0|-1|-1/mgcpapp_invoke_mgcp_sm(2675):[lvl=1]Msg In-Progress(Active) [INVVERB 0], await_ev=0,queued=0x0
Mar 25 2024 12:29:04.457 CDT: //-1/xxxxxxxxxxxx/MGCP|aaln/S0/SU1/0|-1|-1/mgcp_process_deferred_queue(3546):[lvl=0]Entered
Mar 25 2024 12:29:04.457 CDT: //-1/xxxxxxxxxxxx/MGCP/mgcp_store_endpt_and_ntfy_entity_name(4838):[lvl=0]Entered
Mar 25 2024 12:29:04.457 CDT: //-1/xxxxxxxxxxxx/MGCP|aaln/S0/SU1/0|-1|-1/mgcp_idle_crcx(6211):[lvl=2]callp(0x23C3B678), current state CALL_IDLE, event EV_CREATE_CONN
Mar 25 2024 12:29:04.457 CDT: //-1/xxxxxxxxxxxx/MGCP/mgcp_init_modem_relay_params(119):[lvl=0]modem-relay-enabled=0, mr-gw-xid=0
Mar 25 2024 12:29:04.457 CDT: //-1/xxxxxxxxxxxx/MGCP|aaln/S0/SU1/0|-1|-1/mgcp_compute_debugsy_hdr(286):[lvl=0]Building Debugsy header
Mar 25 2024 12:29:04.457 CDT: //-1/02E7AAAB8005/MGCP|aaln/S0/SU1/0|-1|-1/<VOICE>/mgcp_compute_debugsy_hdr(395):[lvl=0]GUID[02E7AAAB8005] assigned to call_id[-1], endpt[aaln/S0/SU1/0], mgcp_call_id[n/a], conn_id[0]
Mar 25 2024 12:29:04.457 CDT: //-1/02E7AAAB8005/MGCP|aaln/S0/SU1/0|-1|-1/<VOICE>/mgcp_allocate_if(8438):[lvl=2]ccAllocateIF failed rc -6 vdbptr 0x3F353338 alloc_vdbptr 0x0
Mar 25 2024 12:29:04.457 CDT: //-1/xxxxxxxxxxxx/MGCP/mgcp_xlate_ccapi_error_code(1115):[lvl=1]ack_code_tab_index = 16, Endpt not available
Mar 25 2024 12:29:04.457 CDT: //-1/xxxxxxxxxxxx/MGCP/mgcp_error_code_to_ack_code(795):[lvl=0]error_tab_index = 16, protocol version: 4

Elliot Dierksen · ‎03-26-2024

Is the gateway possibly running out of memory? It might be worth rebooting it during a maintenance window. Is the gateway failing to allocate a DSP channel? "show voice dsp group all" will give you that information. Is the destination to which this inbound MGCP port is being sent still valid? If it is a shared DN, is it possible that you are hitting the maximum number of calls on that DN?

Clifford McGlamry · ‎03-26-2024

We rebooted it, and the behavior did not change. This is the first port on a 4 port FXO card. Other ports are working fine. I have suggested to the customer to move this particular line to a different port to see if the problem moves. But I haven't heard back yet. It's not a shared extension, and it is valid and reachable.