Retransmission timeout for inbound calls only

Asterisk Asterisk SIP
1

Hi all,
I have the error message below and not able to receive inbound calls but outbound calls are working fine.

[Feb 27 01:55:56] WARNING[1629]: chan_sip.c:4140 retrans_pkt: Retransmission timeout reached on transmission pt8u2ouho3uo0089u266098uzuh90hmu@10.18.5.64 for seqno 1 (Critical Response) – See SIP Retransmissions - Asterisk Project - Asterisk Project Wiki
Packet timed out after 32001ms with no response

So i read the info in the link above and then did a Tcpdump below to see if my firewall or something from my end is blocking the SIP traffic. Is anything blocking the traffic from my end?
I can see ACK in the log below but for some reason, my Server seem not to be getting it, and thus retransmitting the “200 ok” to the SIP provider.
Please note that ipv6 is enabled and all the visisble IPs below are not known to me and they don’t look like my SIP provider IPs.

root@MyServerName:/etc/asterisk# tcpdump -r newtcpdump1
-su: tcpdump -r: command not found
root@MyServerName:/etc/asterisk# tcpdump -r newtcpdump1
reading from file newtcpdump1, link-type EN10MB (Ethernet)
03:53:05.200107 IP 194.147.140.59.43369 > MyServerName.5394: Flags [S], seq 2796229618, win 1024, length 0
03:53:05.200154 IP MyServerName.5394 > 194.147.140.59.43369: Flags [R.], seq 0, ack 2796229619, win 0, length 0
03:53:05.239079 IP 194.147.140.59.43369 > MyServerName.5394: Flags [R], seq 2796229619, win 1200, length 0
03:53:11.033107 IP unassign.5068 > MyServerName.sip: SIP: INVITE sip:SIPuserName@xxxxxx SIP/2.0
03:53:11.533874 IP unassign.5068 > MyServerName.sip: SIP: INVITE sip:SIPuserName@xxxxxx SIP/2.0
03:53:12.527865 IP unassign.5068 > MyServerName.sip: SIP: INVITE sip:SIPuserName@xxxxxx SIP/2.0
03:53:14.520064 IP unassign.5068 > MyServerName.sip: SIP: INVITE sip:SIPuserName@xxxxxx SIP/2.0
03:53:16.030380 IP unassign.5066 > MyServerName.sip: SIP: OPTIONS sip:MyServerIP:5060 SIP/2.0
03:53:18.528351 IP unassign.5068 > MyServerName.sip: SIP: INVITE sip:SIPuserName@xxxxxx SIP/2.0
03:53:26.520993 IP unassign.5068 > MyServerName.sip: SIP: INVITE sip:SIPuserName@xxxxxx SIP/2.0
03:53:27.597946 IP 193.107.216.20.45447 > MyServerName.sip-tls: Flags [S], seq 3354904193, win 1024, length 0
03:53:27.597980 IP MyServerName.sip-tls > 193.107.216.20.45447: Flags [R.], seq 0, ack 3354904194, win 0, length 0
03:53:27.640201 IP 193.107.216.20.45447 > MyServerName.sip-tls: Flags [R], seq 3354904194, win 1200, length 0
03:53:32.031433 IP unassign.5065 > MyServerName.sip: SIP: OPTIONS sip:MyServerIP:5060 SIP/2.0
03:53:35.345921 IP unassign.sip > MyServerName.sip: SIP: SIP/2.0 401 Unauthorized
03:53:35.438023 IP unassign.sip > MyServerName.sip: SIP: SIP/2.0 200 OK
03:53:42.530295 IP unassign.5068 > MyServerName.sip: SIP: INVITE sip:SIPuserName@xxxxxx SIP/2.0
03:53:48.040680 IP unassign.5067 > MyServerName.sip: SIP: OPTIONS sip:MyServerIP:5060 SIP/2.0
03:53:48.168960 IP 193.107.216.16.5236 > MyServerName.sip: SIP: OPTIONS sip:100@MyServerIP SIP/2.0
03:54:15.144607 IP vmi489673.contaboserver.net.55293 > MyServerName.8291: Flags [S], seq 1743448413, win 1024, length 0
03:54:15.144656 IP MyServerName.8291 > vmi489673.contaboserver.net.55293: Flags [R.], seq 0, ack 1743448414, win 0, length 0
03:54:15.162235 IP vmi489673.contaboserver.net.55293 > MyServerName.8291: Flags [R], seq 1743448414, win 1200, length 0
03:54:29.652906 IP 194.147.140.59.43369 > MyServerName.5077: Flags [S], seq 2596479541, win 1024, length 0
03:54:29.652956 IP MyServerName.5077 > 194.147.140.59.43369: Flags [R.], seq 0, ack 2596479542, win 0, length 0
03:54:29.666014 IP 194.147.140.59.43369 > MyServerName.5077: Flags [R], seq 2596479542, win 1200, length 0
03:54:44.008463 IP 85.204.116.88.60592 > MyServerName.http-alt: Flags [S], seq 1603183079, win 49560, length 0
03:54:44.008514 IP MyServerName.http-alt > 85.204.116.88.60592: Flags [R.], seq 0, ack 1603183080, win 0, length 0
03:54:49.483838 IP 194.147.140.23.57484 > MyServerName.33049: Flags [S], seq 586002813, win 1024, length 0
03:54:49.483888 IP MyServerName.33049 > 194.147.140.23.57484: Flags [R.], seq 0, ack 586002814, win 0, length 0
03:54:49.510598 IP 194.147.140.23.57484 > MyServerName.33049: Flags [R], seq 586002814, win 1200, length 0




root@MyServerName:/etc/asterisk# tcpdump portrange 100-40000 -w newtcpdump2
tcpdump: listening on eth0, link-type EN10MB (Ethernet), capture size 262144 bytes
^C50 packets captured
53 packets received by filter
0 packets dropped by kernel
root@MyServerName:/etc/asterisk# tcpdump -r newtcpdump2
reading from file newtcpdump2, link-type EN10MB (Ethernet)
04:15:48.654741 IP 104.248.229.42.49067 > MyServerName.2201: Flags [S], seq 4134702610, win 1024, length 0
04:15:48.654789 IP MyServerName.2201 > 104.248.229.42.49067: Flags [R.], seq 0, ack 4134702611, win 0, length 0
04:15:54.242196 IP 194.147.140.59.43369 > MyServerName.3456: Flags [S], seq 3191332754, win 1024, length 0
04:15:54.242254 IP MyServerName.3456 > 194.147.140.59.43369: Flags [R.], seq 0, ack 3191332755, win 0, length 0
04:15:54.267373 IP 194.147.140.59.43369 > MyServerName.3456: Flags [R], seq 3191332755, win 1200, length 0
04:15:55.503174 IP unassign.5066 > MyServerName.sip: SIP: INVITE sip:SIPuserName@WEB_WAY SIP/2.0
04:15:56.001149 IP unassign.5066 > MyServerName.sip: SIP: INVITE sip:SIPuserName@WEB_WAY SIP/2.0
04:15:56.693868 IP 195.54.161.151.42260 > MyServerName.10474: Flags [S], seq 4104760656, win 1024, length 0
04:15:56.693909 IP MyServerName.10474 > 195.54.161.151.42260: Flags [R.], seq 0, ack 4104760657, win 0, length 0
04:15:56.779644 IP 195.54.161.151.42260 > MyServerName.10474: Flags [R], seq 4104760657, win 1200, length 0
04:15:56.997245 IP unassign.5066 > MyServerName.sip: SIP: INVITE sip:SIPuserName@WEB_WAY SIP/2.0
04:15:58.774824 IP 78.77.89.218.broad.ls.sc.dynamic.163data.com.cn.59145 > MyServerName.ms-sql-s: Flags [S], seq 986038679, win 1024, length 0
04:15:58.774864 IP MyServerName.ms-sql-s > 78.77.89.218.broad.ls.sc.dynamic.163data.com.cn.59145: Flags [R.], seq 0, ack 986038680, win 0, length 0
04:15:59.001359 IP unassign.5066 > MyServerName.sip: SIP: INVITE sip:SIPuserName@WEB_WAY SIP/2.0
04:15:59.475814 IP 78.77.89.218.broad.ls.sc.dynamic.163data.com.cn.59145 > MyServerName.ms-sql-s: Flags [R], seq 986038680, win 1200, length 0
04:16:00.510261 IP unassign.5067 > MyServerName.sip: SIP: OPTIONS sip:95.142.161.231:5060 SIP/2.0
04:16:02.997627 IP unassign.5066 > MyServerName.sip: SIP: INVITE sip:SIPuserName@WEB_WAY SIP/2.0
04:16:09.860084 IP 162.243.232.174.52705 > MyServerName.13135: Flags [S], seq 1619829103, win 1024, length 0
04:16:09.860121 IP MyServerName.13135 > 162.243.232.174.52705: Flags [R.], seq 0, ack 1619829104, win 0, length 0
04:16:11.002320 IP unassign.5066 > MyServerName.sip: SIP: INVITE sip:SIPuserName@WEB_WAY SIP/2.0
04:16:12.012133 IP 92.118.161.1.netsystemsresearch.com.49787 > MyServerName.ftps: Flags [S], seq 3321357605, win 1024, options [mss 1460], length 0
04:16:12.012170 IP MyServerName.ftps > 92.118.161.1.netsystemsresearch.com.49787: Flags [R.], seq 0, ack 3321357606, win 0, length 0
04:16:16.515372 IP unassign.5066 > MyServerName.sip: SIP: OPTIONS sip:95.142.161.231:5060 SIP/2.0
04:16:22.566126 IP unassign.sip > MyServerName.sip: SIP: SIP/2.0 401 Unauthorized
04:16:22.657742 IP unassign.sip > MyServerName.sip: SIP: SIP/2.0 200 OK
04:16:24.522165 IP 194.147.140.59.43369 > MyServerName.4864: Flags [S], seq 2586385048, win 1024, length 0
04:16:24.522217 IP MyServerName.4864 > 194.147.140.59.43369: Flags [R.], seq 0, ack 2586385049, win 0, length 0
04:16:24.557829 IP 194.147.140.59.43369 > MyServerName.4864: Flags [R], seq 2586385049, win 1200, length 0
04:16:26.114837 IP 185.156.73.67.49450 > MyServerName.4380: Flags [S], seq 479817840, win 1024, length 0
04:16:26.114896 IP MyServerName.4380 > 185.156.73.67.49450: Flags [R.], seq 0, ack 479817841, win 0, length 0
04:16:26.143369 IP 185.156.73.67.49450 > MyServerName.4380: Flags [R], seq 479817841, win 1200, length 0
04:16:26.999454 IP unassign.5066 > MyServerName.sip: SIP: INVITE sip:SIPuserName@WEB_WAY SIP/2.0
04:16:31.910025 IP scanner-10.ch1.censys-scanner.com.52395 > MyServerName.3001: Flags [S], seq 3406112237, win 1024, options [mss 1460], length 0
04:16:31.910073 IP MyServerName.3001 > scanner-10.ch1.censys-scanner.com.52395: Flags [R.], seq 0, ack 3406112238, win 0, length 0
04:16:32.516642 IP unassign.5065 > MyServerName.sip: SIP: OPTIONS sip:95.142.161.231:5060 SIP/2.0
04:16:44.357066 IP websec-test.com.57244 > MyServerName.12859: Flags [S], seq 3285725857, win 1024, length 0
04:16:44.357116 IP MyServerName.12859 > websec-test.com.57244: Flags [R.], seq 0, ack 3285725858, win 0, length 0
04:16:44.374579 IP websec-test.com.57244 > MyServerName.12859: Flags [R], seq 3285725858, win 1200, length 0
04:16:56.202269 IP 194.147.140.59.43369 > MyServerName.4111: Flags [S], seq 2893655587, win 1024, length 0
04:16:56.202321 IP MyServerName.4111 > 194.147.140.59.43369: Flags [R.], seq 0, ack 2893655588, win 0, length 0
04:16:56.239829 IP 194.147.140.59.43369 > MyServerName.4111: Flags [R], seq 2893655588, win 1200, length 0
04:16:57.405964 IP 95.142.227.58.62861 > MyServerName.ms-sql-s: Flags [SEW], seq 1863045841, win 8192, options [mss 1460,nop,wscale 8,nop,nop,sackOK], length 0
04:16:57.406001 IP MyServerName.ms-sql-s > 95.142.227.58.62861: Flags [R.], seq 0, ack 1863045842, win 0, length 0
04:16:58.021794 IP 95.142.227.58.62861 > MyServerName.ms-sql-s: Flags [S], seq 1863045841, win 8192, options [mss 1460,nop,wscale 8,nop,nop,sackOK], length 0
04:16:58.021841 IP MyServerName.ms-sql-s > 95.142.227.58.62861: Flags [R.], seq 0, ack 1, win 0, length 0
04:16:58.720821 IP 95.142.227.58.62861 > MyServerName.ms-sql-s: Flags [S], seq 1863045841, win 8192, options [mss 1460,nop,nop,sackOK], length 0
04:16:58.720870 IP MyServerName.ms-sql-s > 95.142.227.58.62861: Flags [R.], seq 0, ack 1, win 0, length 0
04:17:07.872712 IP 194.147.140.59.43369 > MyServerName.4640: Flags [S], seq 3015827598, win 1024, length 0
04:17:07.872761 IP MyServerName.4640 > 194.147.140.59.43369: Flags [R.], seq 0, ack 3015827599, win 0, length 0
04:17:07.889815 IP 194.147.140.59.43369 > MyServerName.4640: Flags [R], seq 3015827599, win 1200, length 0
2

There are no SIP ACKs in the log. The only ACKs are for TCP, and that is being used for TLS, so it is not possible to see what the application level signalling is.

3

This line below with unauthorized seem to be the only negative line in the log, sorry i can’t seem to figure out, please what does it mean?
Am actually trying to see why the ack is not coming from SIP provider to my server, and if anything is blocking it from my end?
03:53:35.345921 IP unassign.sip > MyServerName.sip: SIP: SIP/2.0 401 Unauthorized

4

Unauthorised loosely means “please login”. It should result in an ACK, followed by an INVITE that contains the correct authentication data. It is normal.

5

oh thanks, so it seems nothing is blocking the sip traffic from my end?

6

This topic was automatically closed 30 days after the last reply. New replies are no longer allowed.