一个奇怪的TCP会话脚本

我遇到了一个很奇怪的问题，我想和大家分享一下。 也许你会帮我提出一些想法。

KVM驱动的主机上有3个虚拟机。 其实大概有50个虚拟机，但是他们都工作的很好，虽然这3个虚拟机的行为有点不同寻常。

下面是一个图表，说明这三个虚拟机和它们之间的两个链接：

当一切正常时，这两个之间的TCP会话（“GET / HTTP / 1.0” – “HTTP 200 OK”）如下所示：

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00:58:43.885118 IP 192.168.111.2.55480 > 192.168.113.2.http: Flags [S], seq 926382744, win 14600, options [mss 1460,sackOK,TS val 277997 ecr 0,nop,wscale 7], length 0 00:58:43.885380 IP 192.168.113.2.http > 192.168.111.2.55480: Flags [S.], seq 1849545379, ack 926382745, win 14480, options [mss 1460,sackOK,TS val 3702103 ecr 277997,nop,wscale 7], length 0 00:58:43.885957 IP 192.168.111.2.55480 > 192.168.113.2.http: Flags [.], ack 1, win 115, options [nop,nop,TS val 277998 ecr 3702103], length 0 00:58:43.886000 IP 192.168.111.2.55480 > 192.168.113.2.http: Flags [P.], seq 1:213, ack 1, win 115, options [nop,nop,TS val 277998 ecr 3702103], length 212 00:58:43.886061 IP 192.168.113.2.http > 192.168.111.2.55480: Flags [.], ack 213, win 122, options [nop,nop,TS val 3702104 ecr 277998], length 0 00:58:43.922286 IP 192.168.113.2.http > 192.168.111.2.55480: Flags [P.], seq 1:372, ack 213, win 122, options [nop,nop,TS val 3702140 ecr 277998], length 371 00:58:43.922335 IP 192.168.113.2.http > 192.168.111.2.55480: Flags [F.], seq 372, ack 213, win 122, options [nop,nop,TS val 3702140 ecr 277998], length 0 00:58:43.923150 IP 192.168.111.2.55480 > 192.168.113.2.http: Flags [.], ack 372, win 123, options [nop,nop,TS val 278035 ecr 3702140], length 0 00:58:43.923622 IP 192.168.111.2.55480 > 192.168.113.2.http: Flags [F.], seq 213, ack 373, win 123, options [nop,nop,TS val 278036 ecr 3702140], length 0 00:58:43.923671 IP 192.168.113.2.http > 192.168.111.2.55480: Flags [.], ack 214, win 122, options [nop,nop,TS val 3702142 ecr 278036], length 0 

好的，一切都很好。

然后，我们保存pfSenseconfiguration，销毁这个VM，创build一个新的，从头开始安装pfSense，并从备份文件中恢复configuration。

这就是我们之后看到的：

 00:46:39.218193 IP 192.168.111.2.51674 > 192.168.113.2.http: Flags [S], seq 3622924060, win 14600, options [mss 1460,sackOK,TS val 674608862 ecr 0,nop,wscale 7], length 0 00:46:39.218316 IP 192.168.113.2.http > 192.168.111.2.51674: Flags [S.], seq 152904245, ack 3622924061, win 14480, options [mss 1460,sackOK,TS va l 2977436 ecr 674608862,nop,wscale 7], length 0 00:46:39.218570 IP 192.168.111.2.51674 > 192.168.113.2.http: Flags [.], ack 1, win 115, options [nop,nop,TS val 674608862 ecr 2977436], length 0 00:46:40.417623 IP 192.168.113.2.http > 192.168.111.2.51674: Flags [S.], seq 152904245, ack 3622924061, win 14480, options [mss 1460,sackOK,TS val 2978636 ecr 674608862,nop,wscale 7], length 0 00:46:40.417947 IP 192.168.111.2.51674 > 192.168.113.2.http: Flags [.], ack 1, win 115, options [nop,nop,TS val 674610062 ecr 2977436], length 0 00:46:43.158907 IP 192.168.111.2.51674 > 192.168.113.2.http: Flags [P.], seq 1:17, ack 1, win 115, options [nop,nop,TS val 674612803 ecr 2977436], length 16 00:46:43.360103 IP 192.168.111.2.51674 > 192.168.113.2.http: Flags [P.], seq 1:17, ack 1, win 115, options [nop,nop,TS val 674613004 ecr 2977436], length 16 00:46:43.761787 IP 192.168.111.2.51674 > 192.168.113.2.http: Flags [P.], seq 1:17, ack 1, win 115, options [nop,nop,TS val 674613406 ecr 2977436], length 16 00:46:44.565890 IP 192.168.111.2.51674 > 192.168.113.2.http: Flags [P.], seq 1:17, ack 1, win 115, options [nop,nop,TS val 674614210 ecr 2977436], length 16 00:46:46.174039 IP 192.168.111.2.51674 > 192.168.113.2.http: Flags [P.], seq 1:17, ack 1, win 115, options [nop,nop,TS val 674615818 ecr 2977436], length 16 00:46:49.389921 IP 192.168.111.2.51674 > 192.168.113.2.http: Flags [P.], seq 1:17, ack 1, win 115, options [nop,nop,TS val 674619034 ecr 2977436], length 16 00:46:51.753723 IP 192.168.113.2.http > 192.168.111.2.51672: Flags [F.], seq 1, ack 1, win 114, options [nop,nop,TS val 2989972 ecr 674560137], length 0 00:46:55.821824 IP 192.168.111.2.51674 > 192.168.113.2.http: Flags [P.], seq 1:17, ack 1, win 115, options [nop,nop,TS val 674625466 ecr 2977436], length 16 00:46:57.221625 IP 192.168.113.2.http > 192.168.111.2.51672: Flags [F.], seq 1, ack 1, win 114, options [nop,nop,TS val 2995440 ecr 674560137], length 0 00:47:08.157575 IP 192.168.113.2.http > 192.168.111.2.51672: Flags [F.], seq 1, ack 1, win 114, options [nop,nop,TS val 3006376 ecr 674560137], length 0 00:47:08.685886 IP 192.168.111.2.51674 > 192.168.113.2.http: Flags [P.], seq 1:17, ack 1, win 115, options [nop,nop,TS val 674638330 ecr 2977436], length 16 00:47:30.029609 IP 192.168.113.2.http > 192.168.111.2.51672: Flags [F.], seq 1, ack 1, win 114, options [nop,nop,TS val 3028248 ecr 674560137], length 0 00:47:34.413785 IP 192.168.111.2.51674 > 192.168.113.2.http: Flags [P.], seq 1:17, ack 1, win 115, options [nop,nop,TS val 674664058 ecr 2977436], length 16 00:47:40.478757 IP 192.168.113.2.http > 192.168.111.2.51674: Flags [F.], seq 1, ack 1, win 114, options [nop,nop,TS val 3038697 ecr 674610062], length 0 00:47:34.413785 IP 192.168.111.2.51674 > 192.168.113.2.http: Flags [P.], seq 1:17, ack 1, win 115, options [nop,nop,TS val 674664058 ecr 2977436], length 16 00:47:40.478757 IP 192.168.113.2.http > 192.168.111.2.51674: Flags [F.], seq 1, ack 1, win 114, options [nop,nop,TS val 3038697 ecr 674610062], length 0 00:47:40.479216 IP 192.168.111.2.51674 > 192.168.113.2.http: Flags [FP.], seq 17:19, ack 2, win 115, options [nop,nop,TS val 674670123 ecr 3038697], length 2 00:47:45.946604 IP 192.168.113.2.http > 192.168.111.2.51674: Flags [F.], seq 1, ack 1, win 114, options [nop,nop,TS val 3044165 ecr 674610062], length 0 00:47:45.946979 IP 192.168.111.2.51674 > 192.168.113.2.http: Flags [.], ack 2, win 115, options [nop,nop,TS val 674675591 ecr 3044165,nop,nop,sack 1 {1:2}], length 0 

它看起来像…我不知道，就像他们没有听到对方一样。 他们可以互相ping通，甚至互相交互，但看起来他们只是忽略了一些数据包。

两个虚拟机都显示相同，所以pfSense不会丢弃任何数据包。 虽然似乎有什么错误发生在数据包。 就像他们被某种东西弄坏了一样。

这是我无法理解的，真的。 如果你与我分享任何想法，这将是太棒了。

在此先感谢大家！