GTM Design | LTM+ ASM+GTM on same VM

Hi,

My answers based on a few similar projects:

1- You can have one GTM, but it won't provide true NS redundancy. Best practice I've seen is to have at least two NS geographically separated, each NS pointing to a GTM cluster (2VMs per site to provide in-site F5 redundancy). Other advanced architecture have more NS but same number of F5s by adding secondary ISP link to the mentioned GTMs

2- In theory you can have the three modules in the same VM (I recommend 16GB of RAM) but in practice it's better to have GTM in a separated VM and separated subnet.

3- There's two parts: where to position GTM? and how to handle DNS requests? For the first I usually prefer to have DNS as close as possible to the WAN edge router. For the second, you usually delegate a subdomain, or if managing all your domain by GTM you can point the entire domain to your GTM listeners

4- Two IPs, one for each ISP