Hello,

I found the problem. it is about Kamailio-master. When i test on 5.2 version, it can relay tcp sip request to other side. I think it is a bug for tcp connection.

Thanks.

UAC:IPv6:TCP ---> Kamailio (5.2):IPv6:TCP ---> Kamailio:IPv6:TCP (works)

From: sr-users <sr-users-bounces@lists.kamailio.org> on behalf of YASIN CANER <caner_yaso@hotmail.com>
Sent: Thursday, January 31, 2019 3:01 PM
To: Kamailio (SER) - Users Mailing List
Subject: [SR-Users] ERROR : EAGAIN and write queue full or failed for tcp Connection
 
Hello,

Kamailio gave this error that couldnt bind tcp connection other side. 

Thanks 

Yasin CANER

Kamailio IPv6:TCP: -----> IPv6:TCP Kamailio -----> X ERROR XXXX IPv6:TCP Kamailio
IPv6::C                                IPv6::8                                                         IPv6::5

LOGS: 
 7(15781) DEBUG: <core> [core/msg_translator.c:2937]: create_via_hf(): id added: <;i=1>, rcv proto=2
 7(15781) DEBUG: <core> [core/msg_translator.c:162]: check_via_address(): (FD61:C23C:B3B6:0:0:0:0:C, [FD61:C23C:B3B6:0:0:0:0:C], 0)
 7(15781) DEBUG: <core> [core/tcp_main.c:1977]: tcp_send(): no open tcp connection found, opening new one
 7(15781) DEBUG: <core> [core/ip_addr.c:242]: print_ip(): tcpconn_new: new tcp connection: fd61:c23c:b3b6:0:0:0:0:5
 
 7(15781) DEBUG: <core> [core/tcp_main.c:1229]: tcpconn_new(): on port 5060, type 2
 7(15781) DEBUG: <core> [core/tcp_main.c:1539]: tcpconn_add(): hashes: 507:2382:0, 2
 7(15781) DEBUG: <core> [core/tcp_main.c:2873]: tcpconn_1st_send(): pending write on new connection 0x7fd15b5e7c98 (-1/1483 bytes written) (err: 11 - Resource temporarily unavailable)
 7(15781) ERROR: <core> [core/tcp_main.c:2891]: tcpconn_1st_send(): [FD61:C23C:B3B6:0:0:0:0:5]:5060: EAGAIN and write queue full or failed for 0x7fd15b5e7c98
 7(15781) DEBUG: <core> [core/tcp_main.c:3153]: tcpconn_chld_put(): destroying connection 0x7fd15b5e7c98 (2, -1) flags 0060
 
 7(15781) ERROR: tm [../../core/forward.h:251]: msg_send_buffer(): tcp_send failed
 7(15781) DEBUG: tm [t_fwd.c:1549]: t_send_branch(): send to FD61:C23C:B3B6:0:0:0:0:5:5060 (2) failed
 7(15781) WARNING: tm [t_fwd.c:1567]: t_send_branch(): sending request on branch 0 failed


CONF:

dns_try_ipv6=yes
dns_retr_time=1
dns_retr_no=1
dns_cache_flags=4
tcp_source_ipv6 = [fd61:c23c:b3b6::8]

tcp_async=yes
tcp_rd_buf_size=65536
tcp_wq_blk_size=3000
listen=tcp:[fd61:c23c:b3b6::8]:5060
tcp_connection_lifetime=3605

listen=tcp:[fd61:c23c:b3b6::8]:5060
.....

route[]{
remove_hf("Route");
#loose_route();


if (!is_method("INVITE")) return;
$du="sip: mykamailio1.test:5060;transport=tcp";


if(!t_newtran()){
 xlog("L_WARN"," Couldnt create new transaction \r\n");
 sl_send_reply("503", "Service not available");
 exit;
}

if(!t_relay()){
 send_reply("503", "Service not available");
 exit;
}
exit;
}