Смотрю в логах sl-mon следующую картинку:
13:33:22 [456678] 0: Fxs Pickup
13:33:22 [456678] 0: ==4:GetDtmf
13:33:24 [456694] 0: Fxs Hangup
13:33:24 [456694] 0: ==3:Idle
13:33:24 [456694] 0: SetFax(1)=0
13:33:24 [456694] 0: SetModem(0)=-1
13:40:40 [461050] 0: test=REGISTER
13:40:40 [461050] 1: vladimir=REGISTER
13:40:40 [461050] 0: test=REGISTERFAIL
13:40:40 [461050] SipLineRegStatus=043200
13:40:40 [461050] 1: vladimir=REGISTERFAIL
13:40:40 [461050] SipLineRegStatus=043300
13:41:00 [461253] 0: Register Retry (Last was rejected)
13:41:00 [461253] 0: test=REGISTER
13:41:00 [461253] 1: Register Retry (Last was rejected)
13:41:00 [461254] 1: vladimir=REGISTER
13:41:00 [461254] 0: test=REGISTER_AUTHN
13:41:00 [461254] 1: vladimir=REGISTER_AUTHN
13:41:00 [461254] 0: test=REGISTERED
13:41:00 [461254] SipLineRegStatus=042300
13:41:00 [461255] 1: vladimir=REGISTERED
13:41:00 [461255] SipLineRegStatus=042200
13:50:30 [466957] 0: test=REGISTER
13:50:30 [466958] 1: vladimir=REGISTER
13:50:30 [466958] 0: test=REGISTERFAIL
13:50:30 [466958] SipLineRegStatus=043200
13:50:30 [466958] 1: vladimir=REGISTERFAIL
13:50:30 [466958] SipLineRegStatus=043300
13:50:51 [467165] 0: Register Retry (Last was rejected)
13:50:51 [467165] 0: test=REGISTER
13:50:51 [467165] 1: Register Retry (Last was rejected)
13:50:51 [467166] 1: vladimir=REGISTER
13:50:51 [467166] 0: test=REGISTER_AUTHN
13:50:51 [467166] 1: vladimir=REGISTER_AUTHN
13:50:51 [467166] 0: test=REGISTERED
13:50:51 [467166] SipLineRegStatus=042300
13:50:51 [467167] 1: vladimir=REGISTERED
13:50:51 [467167] SipLineRegStatus=042200
13:52:38 [468233] (S0) Chk RegPxy(0) Dn
13:52:38 [468233] *** Start Dns Query [prokatis.mangosip.ru] 0 #2
13:52:38 [468238] Dn(prokatis.mangosip.ru)=81.88.80.235
14:00:22 [472869] 0: test=REGISTER
14:00:22 [472870] 1: vladimir=REGISTER
14:00:22 [472870] 0: test=REGISTERFAIL
14:00:22 [472870] SipLineRegStatus=043200
14:00:22 [472870] 1: vladimir=REGISTERFAIL
14:00:22 [472870] SipLineRegStatus=043300
14:00:42 [473073] 0: Register Retry (Last was rejected)
14:00:42 [473073] 0: test=REGISTER
14:00:42 [473073] 1: Register Retry (Last was rejected)
14:00:42 [473074] 1: vladimir=REGISTER
14:00:42 [473074] 0: test=REGISTER_AUTHN
14:00:42 [473074] 1: vladimir=REGISTER_AUTHN
14:00:42 [473074] 0: test=REGISTERED
14:00:42 [473074] SipLineRegStatus=042300
14:00:42 [473075] 1: vladimir=REGISTERED
14:00:42 [473075] SipLineRegStatus=042200
14:10:12 [478777] 0: test=REGISTER
14:10:12 [478778] 1: vladimir=REGISTER
14:10:12 [478778] 0: test=REGISTERFAIL
14:10:12 [478778] SipLineRegStatus=043200
14:10:12 [478778] 1: vladimir=REGISTERFAIL
14:10:12 [478778] SipLineRegStatus=043300
14:10:33 [478986] 0: Register Retry (Last was rejected)
14:10:33 [478986] 0: test=REGISTER
14:10:33 [478986] 1: Register Retry (Last was rejected)
14:10:33 [478986] 1: vladimir=REGISTER
14:10:33 [478986] 0: test=REGISTER_AUTHN
14:10:33 [478986] 1: vladimir=REGISTER_AUTHN
14:10:33 [478987] 0: test=REGISTERED
14:10:33 [478987] SipLineRegStatus=042300
14:10:33 [478987] 1: vladimir=REGISTERED
14:10:33 [478987] SipLineRegStatus=042200

не нравится что DVG периодически отваливается ?! в чем прикол ?! кратковременное отключение IP телефонии критично. Что надо подкрутить, мож кто подскажет ?

У Вас сервер отбивает половину запросов регистрации.

Это mango. Как-то исправляется ?!

Обратитесь в поддержку mango