LVS DR mode - Loopback interface creation in real servers

  

Linux servers

           -- create a loopback adaptor with the relevant VIP

        vi /etc/sysconfig/network-scripts/ifcfg-lo:vip1
        enter relevant values as below;

        DEVICE=lo:vip1
        IPADDR=10.1.31.25
        NETMASK=255.255.255.255
        ONBOOT=yes   
        NAME=loopback-lvs-vip
   

          -- disable ARP responses on loopback

               
        vi /etc/sysctl.conf
        append below lines to the file

        net.ipv4.conf.lo.arp_ignore = 1
        net.ipv4.conf.lo.arp_announce = 2
        net.ipv4.conf.all.arp_ignore = 1
        net.ipv4.conf.all.arp_announce = 2

         -- update sysctl values

        sysctl –p

         -- start the loopback adaptor

        ifup lo:vip1

    Windows servers

            -- add a new loopback adaptor via add remove hardware wizard

               
               
         -- first disable the newly created adapter and configure the VIP with the
            netmask 255.255.0.0 temporary. We need to change the netmask to
            255.255.255.255 which can’t be done via interface properties. We need 
            to  update the registry for this.

        

 

          

            -- configure the relevant VIP on loopback interface

                   Now before enabling the loopback device, go to registry and modify
                   the subnet mask.

              

                     Change the highlighted SubnetMask value to 255.255.255.255
                     Close the registry and enable the loopback interface.