Forum Discussion

Ireda's avatar
Ireda
Icon for Cirrus rankCirrus
Feb 19, 2024
Solved

GTM Design | LTM+ ASM+GTM on same VM

Dears, I am planning to publish the same service through two sites by LTM and ASM. Each site has two F5 VMs (LTM and ASM).   The customer is required to make the two sites active-active, we recomm...
security
  • Amine_Kadimi's avatar
    Amine_Kadimi
    Feb 21, 2024

    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

Amr_Ali's avatar
Amr_Ali
Icon for MVP rankMVP

Adding to what Sebastiansierra wrote, you will need to add the two LTM ( LTM Site 1 and LTM Site 2) on the GTM as a Big-IP server, and this method makes the GTM take The status for all Virtual Servers from the LTM, and this you will need to create a virtual server on the GTM and add these Virtual servers to  pool and thin  attach this pool to wideIP with your preferred record, 

you can have just one GTM on one site, and if you plan to get two GTMs one for each site you will need to make synch group between them 

 

 

Ireda's avatar
Ireda
Icon for Cirrus rankCirrus
Feb 21, 2024

Thanks, Amr 

how can I make a synch group between two GTMs in diffrent sites? provide me with a guide.