HAProxy stands for High Availability Proxy, If you are running the Ubuntu Yakkety-16.10 LTS operating system and install  HAProxy-1.6-stable version

execute the below commands to install HAProxy-1.6-stable



# apt-get update



# apt-get install haproxy -t trusty-backports

You will get HAProxy 1.6-stable version, which means you may not a latest one.