iRule for logging LTM

If you have AFM licensed and provisioned, you can use firewall rule logging. Alternatively, if all of your traffic is HTTP and/or DNS, you can you HTTP and DNS logging profiles:

• Using the Request Logging Profile
• Configuring Remote High-Speed DNS Logging

If that's not the case, you could use a simple iRule that logs information for each incoming flow:

when CLIENT_ACCEPTED {
    set hdl [HSL::open -publisher some_publisher]
    HSL::send $hdl "<134> [IP::client_addr] -> [IP::local_addr]"
}

If you want to log higher layer information (e.g., port information), the iRule becomes somewhat more complicated.