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omar05_132659's avatar
omar05_132659
Icon for Nimbostratus rankNimbostratus
Jul 23, 2014

why does BIG IP change ports from one inbound interface to another outbound?

Hello friends,

 

I have just configured a NAT in the F5 in order to handle VPN IPsec Traffic. I got sure about enabling NAT-T in both ends, so the VPN IPsec should have worked fine. But, I did not succeed. I have captured some traffic in the interface which is in the front end and the interface which is in the backend.

 

FRONT END F5´s INTERFACE

 

 

BACK END F5´s INTERFACE

 

 

So, it is the same kind of traffic. Why does the F5 change the port from one interface to the other? I know it is just a source port, buy why 0?

 

Thanks in advance. Any comment will be welcome.

 

OL

 

application delivery
BIG-IP Access Policy Manager (APM)
deployment
LTM
security

1 Reply

  • Arnaud_Lemaire's avatar
    Arnaud_Lemaire
    Icon for Employee rankEmployee
    Jul 28, 2014

    Hello, what is you source-port configuration in VS advanced properties ?

     

    Having 0 as a source port doesn't seem normal to me ... do you have any information in var/log/ltm saying big-ip can't attribute port anymore ?