title: What the tcpdump result mean?
body: <p>I can curl the site on my local, and on my production server.</p>
  
  <p>But I can not curl the site on my staging server.</p>
  
  <p>And On my staging server, I can curl other sites.</p>
  
  <p>the tcpdump result is </p>
  
  <pre><code>2018-03-31 01:16:34.453036 IP (tos 0x0, ttl 64, id 8852, offset 0, flags [DF], proto TCP (6), length 60)
      10.11.112.108.59187 &gt; 192.175.110.124.443: Flags [S], cksum 0xa9d1 (incorrect -&gt; 0x11ef), seq 1631407811, win 29200, options [mss 1460,sackOK,TS val 353791063 ecr 0,nop,wscale 8], length 0
  2018-03-31 01:16:35.452914 IP (tos 0x0, ttl 64, id 8853, offset 0, flags [DF], proto TCP (6), length 60)
      10.11.112.108.59187 &gt; 192.175.110.124.443: Flags [S], cksum 0xa9d1 (incorrect -&gt; 0x10f5), seq 1631407811, win 29200, options [mss 1460,sackOK,TS val 353791313 ecr 0,nop,wscale 8], length 0
  2018-03-31 01:16:37.456926 IP (tos 0x0, ttl 64, id 8854, offset 0, flags [DF], proto TCP (6), length 60)
      10.11.112.108.59187 &gt; 192.175.110.124.443: Flags [S], cksum 0xa9d1 (incorrect -&gt; 0x0f00), seq 1631407811, win 29200, options [mss 1460,sackOK,TS val 353791814 ecr 0,nop,wscale 8], length 0
  2018-03-31 01:16:41.464918 IP (tos 0x0, ttl 64, id 8855, offset 0, flags [DF], proto TCP (6), length 60)
      10.11.112.108.59187 &gt; 192.175.110.124.443: Flags [S], cksum 0xa9d1 (incorrect -&gt; 0x0b16), seq 1631407811, win 29200, options [mss 1460,sackOK,TS val 353792816 ecr 0,nop,wscale 8], length 0
  2018-03-31 01:16:49.480947 IP (tos 0x0, ttl 64, id 8856, offset 0, flags [DF], proto TCP (6), length 60)
      10.11.112.108.59187 &gt; 192.175.110.124.443: Flags [S], cksum 0xa9d1 (incorrect -&gt; 0x0342), seq 1631407811, win 29200, options [mss 1460,sackOK,TS val 353794820 ecr 0,nop,wscale 8], length 0
  2018-03-31 01:17:05.528931 IP (tos 0x0, ttl 64, id 8857, offset 0, flags [DF], proto TCP (6), length 60)
      10.11.112.108.59187 &gt; 192.175.110.124.443: Flags [S], cksum 0xa9d1 (incorrect -&gt; 0xf395), seq 1631407811, win 29200, options [mss 1460,sackOK,TS val 353798832 ecr 0,nop,wscale 8], length 0
  </code></pre>
  
  <p>SO I want to know what happened ? what should I do?</p>