Hello all, i have searched many options but i haven't any new idea. I have 4 openbsd routers (2 on each site). Each router create a GRE tunnel with it's pair.
Here is the configuration: | S1R1 --- gre + ospf --- S2R1 | LAN S1 (OSPF & RIP) | | LAN S2 (OSPF & RIP) | S1R2 --- gre + ospf --- S2R2 | The routing rules are correct, ssh, http(s), smtp, ntp, ldap and many other protocols works as expected between the two sites. But i have a problem with my Avaya phones on S2 which need to contact the S1 gatekeeper. Some packets are lost, and (by sniffing every interface) i don't found where the packets goes. If i capture LAN S1 link, i have this capture: 10:06:24.003479 192.168.238.121.56641 > 192.168.106.38.411: S 2621611805:2621611805(0) win 5840 <mss 1460,sackOK,timestamp 4294948803 0,nop,wscale 4> (DF) 10:06:24.003607 192.168.106.38.411 > 192.168.238.121.56641: S 3090220105:3090220105(0) ack 2621611806 win 5840 <mss 1460,nop,wscale 7> (DF) 10:06:24.018842 192.168.238.121.56641 > 192.168.106.38.411: . ack 1 win 365 (DF) 10:06:24.023582 192.168.238.121.56641 > 192.168.106.38.411: P 1:74(73) ack 1 win 365 (DF) 10:06:24.023710 192.168.106.38.411 > 192.168.238.121.56641: . ack 74 win 46 (DF) 10:06:24.024086 192.168.106.38.411 > 192.168.238.121.56641: . 1:1461(1460) ack 74 win 46 (DF) 10:06:24.024329 192.168.106.38.411 > 192.168.238.121.56641: . 1461:2921(1460) ack 74 win 46 (DF) 10:06:27.017704 192.168.106.38.411 > 192.168.238.121.56641: . 1:1461(1460) ack 74 win 46 (DF) 10:06:33.017772 192.168.106.38.411 > 192.168.238.121.56641: . 1:1461(1460) ack 74 win 46 (DF) 10:06:45.017907 192.168.106.38.411 > 192.168.238.121.56641: . 1:1461(1460) ack 74 win 46 (DF) 10:07:09.018198 192.168.106.38.411 > 192.168.238.121.56641: . 1:1461(1460) ack 74 win 46 (DF) 10:07:57.018732 192.168.106.38.411 > 192.168.238.121.56641: . 1:1461(1460) ack 74 win 46 (DF) 10:08:24.019074 192.168.106.38.411 > 192.168.238.121.56641: FP 2921:4273(1352) ack 74 win 46 (DF) 10:08:24.034803 192.168.238.121.56641 > 192.168.106.38.411: . ack 1 win 365 (DF) If i capture the GRE tunnel i have this capture: 10:06:23.987975 192.168.238.121.56641 > 192.168.106.38.411: S 2621611805:2621611805(0) win 5840 <mss 1460,sackOK,timestamp 4294948803 0,nop,wscale 4> (DF) 10:06:24.003614 192.168.106.38.411 > 192.168.238.121.56641: S 3090220105:3090220105(0) ack 2621611806 win 5840 <mss 1460,nop,wscale 7> (DF) 10:06:24.018833 192.168.238.121.56641 > 192.168.106.38.411: . ack 1 win 365 (DF) 10:06:24.023573 192.168.238.121.56641 > 192.168.106.38.411: P 1:74(73) ack 1 win 365 (DF) 10:06:24.023716 192.168.106.38.411 > 192.168.238.121.56641: . ack 74 win 46 (DF) 10:08:24.019083 192.168.106.38.411 > 192.168.238.121.56641: FP 2921:4273(1352) ack 74 win 46 (DF) 10:08:24.034793 192.168.238.121.56641 > 192.168.106.38.411: . ack 1 win 365 (DF) A part of the TCP transaction disappear and i don't know why. Have you got ideas ??? -- Best regards, Loïc BLOT, UNIX systems, security and network expert http://www.unix-experience.fr