Diagnosing scenario traffic

In this section, we'll take a look at diving into the captured packets and taking a look at how that FTP server is causing some sort of problem with our connectivity. In our last section, we saw some of the basic settings to make sure that the service was running for the FTP server. We took a capture from the client and saw that there was a TCP SYN with some retransmits, so port 21 was not answering. Then, when that service was up and running, we took a look at the server side again and saw that there was still a TCP SYN with some retransmits. There's still something on the server that's not working correctly, and we know it's on the server side (at least, seemingly) because there's a TCP SYN that is arriving at the server. If it's arriving at the server, it's getting through the firewalls at both ends of the connection; it's getting through the routing on the internet, so we know we're getting partway there, but there's something on the server that's not quite...