Hi, Our network environment have Radware Aleton L4 switch, The Aleton L4 switch have one VIP ( the real servers of this VIP are 8 Windows 2008 servers ). All of clients ( at client subnet ) will access to this VIP. The L4 switch and all of Windows 2008 servers are connect to my Layer 3 core switch server subnet, at L4 switch we used DSR function, so we have installed loopback adapter at all of windows 2008 servers and the IP address of loopback adapter is same as L4 switch VIP address. Everything was fine, but yesterday we reboot one of the windows 2008 server, and all clients connected to the server after it reboot complete, not connect to VIP ( it is wrong... ). After we clear my Layer 3 core switch arp table, all of clients connect to L4 VIP correctly. It seems after the server reboot, the server send ARP and the Layer 3 core switch update the VIP arp to this server... Please help to mention me how to resolve this problem? Best Regards, Jackson Ku