Block ICMP for Virtual Server

Perhaps you need to log it to the ltm log file. If you apply this it may provide you with the information you need to block it.

 
  when CLIENT_ACCEPTED {  
  log local0. "The IP Protocol is [IP::protocol]" 
    if { [IP::protocol] == 1 } {  
        reject  
     }  
  }  
 

CB