Forum Discussion

Brandon's avatar
Brandon
Icon for Cirrostratus rankCirrostratus
Apr 22, 2019

insert_xforwarded verification

I have enabled insert_xforwarded oh the Http profile of the VIP.

 

I wanted to verify the F5 was working correctly. What is the best way to verify packet capture or a logging iRule? any examples would be appreciated.

 

Thanks,

 

Brandon

 

application delivery
iRules
LTM
  • Hamish's avatar
    Hamish
    Icon for Cirrocumulus rankCirrocumulus
    May 18, 2019

    The easiest is to tcpdump the traffic (Or ssldump if it's encrypted).

    On the bigip it'd be something like

    tcpdump -i 0.0 -nn  -e -s0 -X host BACKEND_IP_ADDR and port BACKEND_PORT

    -i == specie the interface. 0.0 will snoop all interfaces

    -nn == don't translate ip's or ports to names

    -e == print the link level header when dumping the traffic

    -s0 == capture all packets. Default is just the first 64

    -X == dump the packet as ASCII not just numbers

    The rest is the filter. We want packets that are to/from the backend host and on the port you're talking to.