Duplicate TCP SYN error 419002 in firepower 9300 ASA 9.8(2)

[sandeep4]

Hi all,

In the production network, we are using firepower 9300 with ASA 9.8.2. during NAT translations we are getting " Duplicate TCP SYN from CGN_INTERNET: X.X.X.X/58487 to CGN_INTERNET: X.X.X.X/25268 with different initial sequence number".

please help me to resolve this issue.

Thanks,

sandeep reddy,

[msanlimit]

Looks like you have incorrect NAT rule. My advice is to double check your NAT.