GTM HA sync

The BIG-IP DNS/GTM training exercise at

https://agility17dns-docs.readthedocs.io/en/latest/

may once have been a true "latest", but as of this writing it is a few

years old, and a couple of details of BIG-IP DNS have changed.

The exercise was based on BIG-IP software Release 12.1.x, but one notable

change to the user interface was incorporated beginning with Release 13.1.0.

When configuring...

DNS >> GLSB : Servers : Server.List >> New.Server

...and you get to the step for adding a BIG-IP device, the old GUI

screen would allow you to choose between a standalone BIG-IP system

and a 2-member DSC (HA) setup, with separate server-type choices:

BIG-IP System (Single)

BIG-IP System (Redundant)  [that is, an HA pair of 2 systems]

With Release 13.0 (and later), the "General Properties/Product" choices

offer only a combined type "BIG-IP System" -- but to the menu was added

a "Devices" section. Within this "BIG-IP System Devices" block there is

a small (and easily overlooked) button marked "Add". When you click this

little button, the webpage pops up a box "Add BIG-IP System Device" for

entering IP addresses and other parameters of one BIG-IP system. The

"Add" function can be invoked multiple times, thus supporting DSC groups

containing more than 2 BIG-IP systems.