If the
Application Command Center (ACC) on
your firewall indicates a GTP problem that you want to troubleshoot,
select and look for the GTP packet
capture icon (

) at the beginning
of rows that capture troublesome GTP packets. In those rows you’ll
see the GTP Event Type (such as Abnormal GTPv2-C message with missing
mandatory IE), the Subscriber Identity (IMSI), source and destination
IP address of the packet, and other information.