TCP Handshake completing but not much data

[Gihzmo]

I have a secondary internet connection that i am in the process of setting up, we have a PIX firewall which sits on the outside against the world. The problem I am having is when i access a web site, or when i ping a web site, i do not get a reply the first try, only when i refresh 1 or 2 more times do i get the full page. I put a packet sniffer on the port between the switch and the PIX (the switch is a layer 3 it is doing some routing) and found that each time it tried to make a connection, the handshake was going through, (SYN, SYN ACK, ACK) and then i get little to no data, and the Handshake finishes, (FIN ACK, ACK, FIN ACK) then when i refresh the page, another handshake starts and a little bit more data comes through, sometimes everything comes through on this connection but sometimes not. Then that handshake finishes and another starts and usually by the third connection the data starts coming in, and i see the whole page start to load. I am not sure what would be causing this or how to even begin troubleshooting it. Any help would be Greatly appreciated.

 

[LloydSev]

Well.. you should not really be using the PIX to designate any routing.. if you must, it should be absolutely minimal.

Secondly, are you using a proxy? The router after the PIX, does it's default route point to the PIX? Does the PIX have a default route to the router?

You may find more help in the "Cisco Systems: PIX Firewall" forum also.

Computer/Network Technician
CCNA

 

[bcastner]

Check your MTU settings. A good way to do this is to test:

http://www.dslreports.com/tweaks

 

[Gihzmo]

I am not actually routing anything with the firewall, the layer 3 switch is handling internal routing and routing traffic to the firewall, and the firewall is just forwarding everything (that passess ACL's and such) to our ISP's managed router. On the desktop, we do not have a problem when we go through our main internet connection, so i know that it is not a problem at the desktop. We have narrowed the problem to the PIX, i just do not know what could be causing the problem.