Server side configuration to be compatible with an ALOHA Load-Balancer configured in Layer 4 DSR mode.
DSR (stands for Direct Server Return) is also known as gateway mode.
v4.2 and later
In layer 4 gateway mode, the ALOHA Load-Balancer sees only the traffic going from the client to the server. The servers answer directly to the client through its default gateway.
As shown in the diagram above:
And this is where you need the current document to know how to configure your servers properly.
Create a loopback interface (ie lo:1) with the Virtual IP address and a netmask value setup to 255.255.255.255 (/32).
Don’t forget to make it resilient at start up. This configuration depends on the Linux distribution you’re using.
Setup the two sysctls below:
To apply the changes directly, run the commands below:
sysctl -w net.ipv4.conf.all.arp_ignore=1 sysctl -w net.ipv4.conf.all.arp_announce=2
In order to makes these changes resilient after reboot, edit your /etc/sysctls.conf file then add the two lines below: