Need assistance F5 GTM config .

Hey all,

I'm new to F5 and planning to install first F5 Big-ip LTM + GTM to load balance proxy traffic at two sites which will act as backup to each other. F5 is inline between users >> Proxy Servers >> Internet.

Here is the network diagram of two sites. https://imgur.com/a/sSN8Q1L

Goal is to set up LTM+GTM for traffic processing and failover as below: Normal operation: 1) When Site-A F5 receive DNS query from Site-A LDNS >> Send it to Site A Vip. When Site-A F5 receive DNS query from Site-B LDNS >> Send it to Site B Vip. 2) When Site-B F5 receive DNS query from Site-B LDNS >> Send it to Site B Vip. When Site-B F5 receive DNS query from Site-A LDNS >> Send it to Site A Vip Failover operation: 3) When Site-A F5 receive DNS Query >> If Site A Vip is Down >> Send it to Site-B Vip 4) When Site-B F5 Receive DNS Query >> If Site B Vip is Down >> Send it to Site-A Vip

Here are the ips for example: Site-A Virtual Server= 10.1.1.100 Real server =10.1.2.10 & 20
(10.1.1.100 =webproxy.technet.com 10.1.1.x = internal vlan 10.1.2.x=external vlan) Site-B Virtual Server= 10.2.1.100 Real server =10.2.2.10 & 20
(10.2.1.100 =webproxy.technet.com 10.2.1.x = internal vlan 10.2.2.x=external vlan)

I did the basic config for LTM like node, pool & virtual server. But I’m confused what ip to use for GTM and how to configure GTM to provide name resolution based on client DNS server and irules to divert traffic.

What config do I need on LTM + GTM?? LTM: 1) Configure Node – Real servers ( 10.1.2.10& 20) 2) Configure Pool – Proxy Server Pool ( Add node + port) 3) Config Virtual Server – (webproxy.technet.com/10.1.1.100)

GTM/DNS 1) Config Listener (Can I use Vip??? Or need new ip?? ) 2) Config Wide ip (Do I need different ip in same internal subnet 10.1.1.x??) Does the hostname should be webproxy.technet.com??) 3) Do I need GSLBPool?? What type, SRV, A, CNAME??? Which Member ip to add, wide ip of both site??? 4) Config Data Center- Site-A & site-B 5) Do I need GSLBServer?? Which server to add Vip or Real??? 6) Where do I apply rule to divert traffic?? Under Wide IP???

When user send DNS request for webproxy.technet.com which ip will resolve it Wide ip?? Or Vip??

Does anyone know hierarchy chart for GTM config? Like LTM (node >> pool >> Virtual server). Could someone provide a break down of the objects and config?

Thanks in advance.