High availability in 10.2 and 11.6

HA changed quite a bit between 10 and 11, see this document:

https://support.f5.com/kb/en-us/products/big-ip_ltm/manuals/product/tmos-active-standby-upgrade-11-1-0/1.html

it (mentions 11.1, but same goes for 11.6) explains about the new method with device groups and traffic groups. those should have been created during the upgrade process, but if they aren't you will know where to find them.