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mrshaggy_169440's avatar
mrshaggy_169440
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Jan 14, 2016

APM No Back-end Request/Response on Web Application Trace

Hi all,   We have APM on our system that we used to publish some application using VPN access. We plan to add another portal access list. So we add one more portal access list and add this new por...
application delivery
big-ip
BIG-IP Access Policy Manager (APM)
mrshaggy_169440's avatar
mrshaggy_169440
Icon for Nimbostratus rankNimbostratus
Jan 14, 2016

If we I do a tcpdump during user access test using VPN, it show a lot of TCP SYN retransmission. It seem like the SYN packet from F5 was not received by server, or the SYN-ACK packet from server was not receive by F5, so F5 keep sending the SYN packet. But as I mention previously, if I do curl from F5 into server, F5 get the proper response from server. So it means that basically F5 can reach the server, but I don't know why F5 can't access the server during user VPN session that makes F5 keep sending SYN packet to server..