Any problems with having an active/active HAProxy setup with Keepalived

The important considerations not to have an active/active setup with two virtual IP addresses for the same resource is

• how do you distribute requests over the two virtual IP's
• how do you deal with sticky sessions, affinity, persistence and such, i.e. what happens when subsequent requests start off going to virtual IP1 and then go to virtual IP2 and do you need those to go the same back-end server.
• what happens when the virtual IP-addresses fails over to the other host?