Learning OpenStack Networking - Third Edition

Session persistence

LBaaS v2 supports session persistence on virtual IPs. Session persistence is a method of load balancing that forces multiple client requests of the same protocol to be directed to the same node. This feature is commonly used with many web applications that do not share application states between pool members.

The types of session persistence supported with the HAProxy driver include the following:

• SOURCE_IP
• HTTP_COOKIE
• APP_COOKIE

Using the SOURCE_IP persistence type configures HAProxy with the following settings within the backend pool configuration:

stick-table type ip size 10k 
stick on src

The first time a client connects to the virtual IP, HAProxy creates an entry in a sticky table based on the client's IP address ...