keepalived doing a lot of TCP DUP ACK and TCP Retransmission

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http://serverfault.com – I'm trying to replicate the setup our hosting provider have done for our load balancer, which is using keepalived. So I have one "load balancer", running CentOS 6 and keepalived 1.2.7, with two Web servers running Ubuntu 12.04 LTS and Apache 2.2. If I query one of the two Web servers directly, it's working fine, I get the response in a couple of miliseconds. But if I try to query the Web site by the load balancer, it takes one minute to get the response. I fired up wireshark on the load balancer, and I see a lot of TCP DUP ACK and TCP Retransmission, from both sides (my Mac and the load bala (HowTos)