状況：同一のIPアドレスより69回線のregisterが存在し、突然registerできなくなる現象。

ななんと！Grandstream GS-GXP2170の問題ではなかった。
一箇所のIPV4より69回線が問題だったのです。

Nov 29 12:46:00 sp9 /usr/sbin/watsipproxy[7421]: ALERT: ＜script＞: ALERT: pike blocking REGISTER from sip:1234522@sp.voiplus.net (IP:From.Guest.Public.IP:61595)
Nov 29 12:48:10 sp9 /usr/sbin/watsipproxy[7437]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:202@V.O.I.P (IP:INVITE:69.175.42.79:5070)
Nov 29 12:48:10 sp9 /usr/sbin/watsipproxy[7422]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:202@V.O.I.P (IP:INVITE:69.175.42.79:5071)
Nov 29 12:51:04 sp9 /usr/sbin/watsipproxy[7416]: ALERT: ＜script＞: ALERT: pike blocking REGISTER from sip:1234606@sp.voiplus.net (IP:From.Guest.Public.IP:60226)
Nov 29 12:54:36 sp9 /usr/sbin/watsipproxy[7433]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:1000@V.O.I.P (IP:INVITE:69.175.42.79:5070)
Nov 29 12:54:36 sp9 /usr/sbin/watsipproxy[7415]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:1000@V.O.I.P (IP:INVITE:69.175.42.79:5070)
Nov 29 12:56:06 sp9 /usr/sbin/watsipproxy[7422]: ALERT: ＜script＞: ALERT: pike blocking REGISTER from sip:1234234@sp.voiplus.net (IP:From.Guest.Public.IP:60234)
Nov 29 13:01:02 sp9 /usr/sbin/watsipproxy[7432]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:1000@V.O.I.P (IP:INVITE:69.175.42.79:5070)
Nov 29 13:01:02 sp9 /usr/sbin/watsipproxy[7422]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:1000@V.O.I.P (IP:INVITE:69.175.42.79:5070)
Nov 29 13:01:08 sp9 /usr/sbin/watsipproxy[7417]: ALERT: ＜script＞: ALERT: pike blocking REGISTER from sip:1234221@sp.voiplus.net (IP:From.Guest.Public.IP:60221)
Nov 29 13:06:13 sp9 /usr/sbin/watsipproxy[7421]: ALERT: ＜script＞: ALERT: pike blocking REGISTER from sip:1234245@sp.voiplus.net (IP:From.Guest.Public.IP:62693)
Nov 29 13:07:27 sp9 /usr/sbin/watsipproxy[7434]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:1000@V.O.I.P (IP:INVITE:69.175.42.79:5070)
Nov 29 13:07:27 sp9 /usr/sbin/watsipproxy[7416]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:1000@V.O.I.P (IP:INVITE:69.175.42.79:5076)
Nov 29 13:11:16 sp9 /usr/sbin/watsipproxy[7421]: ALERT: ＜script＞: ALERT: pike blocking REGISTER from sip:1234221@sp.voiplus.net (IP:From.Guest.Public.IP:60221)
Nov 29 13:13:49 sp9 /usr/sbin/watsipproxy[7433]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:1000@V.O.I.P (IP:INVITE:69.175.42.79:5070)
Nov 29 13:13:49 sp9 /usr/sbin/watsipproxy[7415]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:1000@V.O.I.P (IP:INVITE:69.175.42.79:5072)
Nov 29 13:16:19 sp9 /usr/sbin/watsipproxy[7422]: ALERT: ＜script＞: ALERT: pike blocking REGISTER from sip:1234214@sp.voiplus.net (IP:From.Guest.Public.IP:60214)
Nov 29 13:20:14 sp9 /usr/sbin/watsipproxy[7432]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:1000@V.O.I.P (IP:INVITE:69.175.42.79:5070)
Nov 29 13:20:14 sp9 /usr/sbin/watsipproxy[7418]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:1000@V.O.I.P (IP:INVITE:69.175.42.79:5071)
Nov 29 13:21:23 sp9 /usr/sbin/watsipproxy[7415]: ALERT: ＜script＞: ALERT: pike blocking REGISTER from sip:1234950@sp.voiplus.net (IP:From.Guest.Public.IP:60144)
Nov 29 13:26:27 sp9 /usr/sbin/watsipproxy[7422]: ALERT: ＜script＞: ALERT: pike blocking REGISTER from sip:1234522@sp.voiplus.net (IP:From.Guest.Public.IP:61595)
Nov 29 13:26:46 sp9 /usr/sbin/watsipproxy[7436]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:1000@V.O.I.P (IP:INVITE:69.175.42.79:5070)
Nov 29 13:26:47 sp9 /usr/sbin/watsipproxy[7421]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:1000@V.O.I.P (IP:INVITE:69.175.42.79:5070)
Nov 29 13:31:29 sp9 /usr/sbin/watsipproxy[7417]: ALERT: ＜script＞: ALERT: pike blocking REGISTER from sip:1234251@sp.voiplus.net (IP:From.Guest.Public.IP:63210)
Nov 29 13:33:18 sp9 /usr/sbin/watsipproxy[7436]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:1000@V.O.I.P (IP:INVITE:69.175.42.79:5071)
Nov 29 13:33:18 sp9 /usr/sbin/watsipproxy[7417]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:1000@V.O.I.P (IP:INVITE:69.175.42.79:5070)
Nov 29 13:36:31 sp9 /usr/sbin/watsipproxy[7422]: ALERT: ＜script＞: ALERT: pike blocking REGISTER from sip:1234244@sp.voiplus.net (IP:From.Guest.Public.IP:60244)
Nov 29 13:39:43 sp9 /usr/sbin/watsipproxy[7437]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:1000@V.O.I.P (IP:INVITE:69.175.42.79:5070)
Nov 29 13:39:43 sp9 /usr/sbin/watsipproxy[7418]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:1000@V.O.I.P (IP:INVITE:69.175.42.79:5071)
Nov 29 13:41:36 sp9 /usr/sbin/watsipproxy[7418]: ALERT: ＜script＞: ALERT: pike blocking REGISTER from sip:1234233@sp.voiplus.net (IP:From.Guest.Public.IP:60233)
Nov 29 13:46:20 sp9 /usr/sbin/watsipproxy[7434]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:444@V.O.I.P (IP:INVITE:69.175.42.79:5070)
Nov 29 13:46:20 sp9 /usr/sbin/watsipproxy[7421]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:444@V.O.I.P (IP:INVITE:69.175.42.79:5070)
Nov 29 13:46:40 sp9 /usr/sbin/watsipproxy[7419]: ALERT: ＜script＞: ALERT: pike blocking REGISTER from sip:1234504@sp.voiplus.net (IP:From.Guest.Public.IP:60504)
Nov 29 13:51:42 sp9 /usr/sbin/watsipproxy[7416]: ALERT: ＜script＞: ALERT: pike blocking REGISTER from sip:1234254@sp.voiplus.net (IP:From.Guest.Public.IP:60254)
Nov 29 13:52:37 sp9 /usr/sbin/watsipproxy[7437]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:444@V.O.I.P (IP:INVITE:69.175.42.79:5070)
Nov 29 13:52:37 sp9 /usr/sbin/watsipproxy[7418]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:444@V.O.I.P (IP:INVITE:69.175.42.79:5076)
Nov 29 13:56:45 sp9 /usr/sbin/watsipproxy[7415]: ALERT: ＜script＞: ALERT: pike blocking REGISTER from sip:1234706@sp.voiplus.net (IP:From.Guest.Public.IP:60245)
Nov 29 13:58:57 sp9 /usr/sbin/watsipproxy[7438]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:444@V.O.I.P (IP:INVITE:69.175.42.79:5071)
Nov 29 13:58:57 sp9 /usr/sbin/watsipproxy[7416]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:444@V.O.I.P (IP:INVITE:69.175.42.79:5071)
Nov 29 14:01:47 sp9 /usr/sbin/watsipproxy[7419]: ALERT: ＜script＞: ALERT: pike blocking REGISTER from sip:1234252@sp.voiplus.net (IP:From.Guest.Public.IP:60252)
Nov 29 14:05:23 sp9 /usr/sbin/watsipproxy[7432]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:444@V.O.I.P (IP:INVITE:69.175.42.79:5071)
Nov 29 14:05:23 sp9 /usr/sbin/watsipproxy[7416]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:444@V.O.I.P (IP:INVITE:69.175.42.79:5070)
Nov 29 14:06:50 sp9 /usr/sbin/watsipproxy[7415]: ALERT: ＜script＞: ALERT: pike blocking REGISTER from sip:1234253@sp.voiplus.net (IP:From.Guest.Public.IP:60253)
Nov 29 14:11:54 sp9 /usr/sbin/watsipproxy[7432]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:444@V.O.I.P (IP:INVITE:69.175.42.79:5070)
Nov 29 14:11:54 sp9 /usr/sbin/watsipproxy[7416]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:444@V.O.I.P (IP:INVITE:69.175.42.79:5074)
Nov 29 14:12:12 sp9 /usr/sbin/watsipproxy[7420]: ALERT: ＜script＞: ALERT: pike blocking REGISTER from sip:1234242@sp.voiplus.net (IP:From.Guest.Public.IP:60242)
Nov 29 14:17:17 sp9 /usr/sbin/watsipproxy[7417]: ALERT: ＜script＞: ALERT: pike blocking REGISTER from sip:1234704@sp.voiplus.net (IP:From.Guest.Public.IP:60704)
Nov 29 14:18:24 sp9 /usr/sbin/watsipproxy[7431]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:444@V.O.I.P (IP:INVITE:69.175.42.79:5071)
Nov 29 14:18:24 sp9 /usr/sbin/watsipproxy[7421]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:444@V.O.I.P (IP:INVITE:69.175.42.79:5074)
Nov 29 14:22:19 sp9 /usr/sbin/watsipproxy[7419]: ALERT: ＜script＞: ALERT: pike blocking REGISTER from sip:1234241@sp.voiplus.net (IP:From.Guest.Public.IP:60241)
Nov 29 14:24:52 sp9 /usr/sbin/watsipproxy[7433]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:444@V.O.I.P (IP:INVITE:69.175.42.79:5071)
Nov 29 14:24:52 sp9 /usr/sbin/watsipproxy[7420]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:444@V.O.I.P (IP:INVITE:69.175.42.79:5070)
Nov 29 14:27:26 sp9 /usr/sbin/watsipproxy[7421]: ALERT: ＜script＞: ALERT: pike blocking REGISTER from sip:1234254@sp.voiplus.net (IP:From.Guest.Public.IP:60254)
Nov 29 14:31:16 sp9 /usr/sbin/watsipproxy[7438]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:444@V.O.I.P (IP:INVITE:69.175.42.79:5074)
Nov 29 14:31:16 sp9 /usr/sbin/watsipproxy[7417]: ALERT: ＜script＞: ERROR BLOCKING FORCECALL from 69.175.42.79 USER is sip:444@V.O.I.P (IP:INVITE:69.175.42.79:5070)
Nov 29 14:32:29 sp9 /usr/sbin/watsipproxy[7422]: ALERT: ＜script＞: ALERT: pike blocking REGISTER from sip:1234214@sp.voiplus.net (IP:From.Guest.Public.IP:60214)
Nov 29 14:37:31 sp9 /usr/sbin/watsipproxy[7420]: ALERT: ＜script＞: ALERT: pike blocking REGISTER from sip:1234233@sp.voiplus.net (IP:From.Guest.Public.IP:60233)

Anti SIP Floodでbanされてました。（ガーーーン）
ってことで、sipproxyのconfigを修正しました。

# —– pike params —–
#modparam(“pike”, “sampling_time_unit”, 2)
#modparam(“pike”, “reqs_density_per_unit”, 16)
#modparam(“pike”, “remove_latency”, 4)
modparam(“pike”, “sampling_time_unit”, 2)
modparam(“pike”, “reqs_density_per_unit”, 30)
modparam(“pike”, “remove_latency”, 4)
modparam(“pike”, “pike_log_level”, -1)

これで、更に監視します。
2017-11-29　14:45に復旧しましたん。

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