Hi, I have attached a network diagram with a topology that is causing some problems. There is an AIX Server doing up/down monitoring of Windows Servers (top to bottom in the diagram). When sending 100 packets, we drop about 2 or 3. These are not always the first packet either, could be in the middle of the ping session. I ran sniffer traces at every hop and found that the echo-reply goes into the 6509-01, coming from Cust FW but doesn't come back out of the 6509-01 towards the SNI FW. The 6509 is L3 routing between SNI FW and Cust FW. Arp entries do exist on the 6509 for the AIX Natted IP. The 6509 is running a sup2/msfc2 on 12.2.18(SXD7). It currently only has 32mb Flash, need more to upgrade code level. Anybody have any suggestions what might be causing this or troubleshooting tips to track it down? Cheers, Brian